Power generation system

Abstract

To make effective use of surplus power by suppressing the storage of power.SOLUTION: A power generation system includes a steam turbine 2 that generates power, a renewable energy generation facility 11 that is connected to a power system 1, and steam generation means 12 for generating steam to drive the steam expansion turbine 2 using surplus power from the power generated by the renewable energy generation facility 11. The power generation system uses the surplus of power generated by the renewable energy generation facility 11 to drive the steam turbine 2 with steam generated by the steam generation means 12, and a parallel operation that maintains no transmission end output is provided by the surplus of power.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a power generation system that can effectively utilize surplus power. [Background technology]

[0002] Thermal power plants that use fuels such as coal and natural gas are widely used as power generation facilities that can stably meet power demand. To ensure stable operation of the power grid, thermal power plants are required to maintain a power generation state and adjust power supply and demand by increasing or decreasing output, as well as to maintain the inertial force of generators and turbines within the power grid and to supply reactive power to the power grid using generators. In other words, parallel operation is required to maintain a power generation state even when there is no sending-end output.

[0003] Meanwhile, as one of the countermeasures against global warming, reduction of carbon dioxide emitted from power plants etc. has been considered recently. Against this background, renewable energy power generation facilities that use renewable energy instead of coal or natural gas, which emit carbon dioxide, are being introduced (for example, Patent Document 1).

[0004] Because the output of renewable energy power generation facilities varies greatly depending on the natural environment, it is inevitable that surplus electricity will be generated at certain times of the day. In order to effectively utilize surplus electricity, there is currently a need for large-capacity, inexpensive energy storage. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-226238 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a power generation system that can effectively utilize surplus power. [Means for solving the problem]

[0007] To achieve the above object, the power generation system of the present invention according to claim 1 comprises an expansion turbine that is driven by the expansion of a fluid to generate power, a renewable energy power generation facility connected to an electric power grid, and fluid generating means that generates a fluid that drives the expansion turbine using surplus power from the power generated by the renewable energy power generation facility, The expansion turbine is driven by the fluid generated by the fluid generating means, and the inertial force of at least the generator and the expansion turbine is maintained in the power system, thereby performing parallel operation in which no power output is maintained at the sending end. It is characterized by:

[0008] In the present invention according to claim 1, surplus electricity generated by the renewable energy power generation facility can be used to generate fluid by fluid generating means to drive an expansion turbine. The fluid generating means can be, for example, an electric heater or heat pump that heats feedwater to generate steam or that heats stored air to obtain a high-temperature, high-pressure working fluid. In addition, by using the fluid obtained from surplus electricity to drive an expansion turbine, it becomes possible to adjust the supply and demand of electricity by increasing or decreasing the output, maintain the inertial force of the generator and turbine within the power system, and supply reactive power to the power system using the generator, thereby using the surplus electricity to cover parallel operation that maintains a state where there is no output at the sending end.

[0009] Therefore, the power generation system of the present invention can effectively utilize surplus power by suppressing the storage of power.

[0012] Also, Claim 2 The power generation system of the present invention relates to Claim 1 In the power generation system described in the above, the expansion turbine is a steam turbine supplied with steam generated in a boiler that obtains steam by burning fuel.

[0013] Claim 2 In the present invention, the fluid (steam generated by the fluid generating means) obtained by surplus electricity can be used to drive a steam turbine that generates electricity using steam generated in a boiler that uses coal, oil, or natural gas as fuel.

[0014] Also, Claim 3The power generation system of the present invention relates to Claim 1 In the power generation system described in the above, the expansion turbine is a steam turbine supplied with steam generated in a heat recovery boiler that obtains steam from exhaust gas of a gas turbine.

[0015] Claim 3 In the present invention, a fluid obtained by surplus electricity (steam obtained by a fluid generating means) can be used to drive a steam turbine that generates electricity using steam generated in a heat recovery boiler that obtains steam from exhaust gas from a gas turbine. Also, a fluid heated by surplus electricity (high-temperature, high-pressure fluid obtained by a fluid generating means) can be used to drive a gas turbine that generates electricity using combustion gas.

[0016] Also, Claim 4 The power generation system of the present invention relates to Claim 1 In the power generation system described above, the expansion turbine is an expansion turbine that obtains power generation power to obtain a power source and a heat source used in industrial facilities (factories).

[0017] Claim 4 In the present invention, for example, a fluid (fluid generated by a fluid generating means) generated by surplus power can be used to drive an expansion turbine that generates power and heat for use in an industrial facility (factory). For example, when the industrial facility (factory) is stopped, the surplus power can be used to cover the parallel operation of expansion turbines that generate power and heat (steam). Also, for example, when the power for the industrial facility (factory) is supplied by relatively inexpensive power, it becomes possible to perform parallel operation of expansion turbines that generate only heat (steam). [Effects of the Invention]

[0018] The power generation system of the present invention makes it possible to suppress the storage of power and effectively utilize surplus power. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic system diagram of a power generation system according to a first embodiment of the present invention. [Figure 2] FIG. 5 is a schematic system diagram of a power generation system according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a schematic system diagram of a power generation system according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] FIG. 1 shows a schematic system for explaining the overall configuration of a power generation system according to a first embodiment of the present invention.

[0021] A thermal power plant 4 is connected to the power grid 1. The thermal power plant 4 generates electricity by operating a generator 3 driven by a steam turbine 2, which is an expansion turbine. The thermal power plant 4 has a boiler 6 in which fuel, for example, coal (pulverized coal), is fed into a combustion chamber 5 to generate steam.

[0022] The high-temperature, high-pressure steam generated in the boiler 6 is sent to the steam turbine 2 through the steam inlet 7 and expanded (driving the steam turbine 2), rotating the generator 3. After completing its work in the steam turbine 2, the exhaust steam is condensed in the condenser and supplied to the boiler 6.

[0023] On the other hand, a renewable energy power generation facility 11 that obtains power from renewable energy (wind power, solar power, etc.) is connected to the power grid 1. The load of the power grid 1 is covered by the power obtained by the thermal power generation facility 4 and the power obtained by the renewable energy power generation facility 11. It has become like this.

[0024] The renewable energy power generation facility 11 inevitably generates surplus power at certain times of the day because its output varies greatly depending on the natural environment. For this reason, the facility is provided with steam generating means 12 (fluid generating means: electric heater, heat pump, etc.) that generates steam as a fluid using the surplus power obtained by the renewable energy power generation facility 11 and supplied to the power grid 1.

[0025] The steam generated by the steam generating means 12 can be sent to the steam turbine 2 via the switching means 13. By supplying steam from the steam generating means 12 to the steam turbine 2 via the switching means 13, the steam turbine 2 can be driven by surplus electricity from the electricity obtained by the renewable energy power generation facility 11.

[0026] The energy of the steam turbine 2 driven by the surplus electricity is used to adjust the supply and demand of electricity by increasing or decreasing the output, to maintain the inertial force of rotating bodies such as the steam turbine 2 and the generator 3 within the power system, and to supply reactive power to the power system 1 using the generator 3, thereby providing parallel operation that maintains a state where there is no output at the sending end.

[0027] The output of the steam turbine 2 is increased or decreased by adjusting the output through open / close control (partially closed operation, throttling operation, etc.) of the steam passage of the steam supplied to the steam turbine 2. The output of the steam turbine 2 is also increased or decreased by controlling the output of the electric heater, heat pump, etc. of the steam generating means 12 to adjust (store) the pressure of the steam supplied to the steam turbine 2.

[0028] The power generation system configured as described above can perform parallel operation in which the excess power obtained from the renewable energy power generation facility 11 and supplied to the power grid 1 is used to generate steam to drive the steam turbine 2 (not using the steam obtained from the thermal power generation facility 4), thereby maintaining a state in which there is no power at the sending end.

[0029] Therefore, for operations to cover the adjustment power, such as adjusting the power supply and demand by increasing or decreasing the output, maintaining the inertial force of rotating bodies such as the steam turbine 2 and the generator 3 within the power system, and operating the generator 3 to supply reactive power to the power system 1, there is no need to use steam generated by the boiler 6 (without using fuel such as coal or oil), and it becomes possible to carry out operations to cover the adjustment power (operations maintaining a parallel state) with zero emissions.

[0030] Therefore, in the power generation system described above, it becomes possible to effectively utilize the surplus power generated by the renewable energy power generation facility 11 without storing the surplus power.

[0031] A second embodiment of the present invention will be described with reference to FIG.

[0032] Fig. 2 shows a schematic system for explaining the overall configuration of a power generation system according to a second embodiment of the present invention. Note that the same members as those shown in Fig. 1 are given the same reference numerals and their explanations are omitted.

[0033] The power generation system shown in Figure 2 includes a gas turbine facility 21, a heat recovery boiler 22 that generates steam using exhaust gas from the gas turbine facility 21, and a steam turbine facility 23 that generates electricity using the steam obtained in the heat recovery boiler 22 (combined power generation facility).

[0034] The gas turbine facility 21 is equipped with a combustor 26 to which air compressed by a compressor 25 and fuel are sent to produce combustion gas. The high-temperature, high-pressure combustion gas from the combustor 26 is sent to an expansion turbine 27, where the high-temperature, high-pressure combustion gas is expanded to drive a generator 28. The exhaust gas from the expansion turbine 27 is sent to a heat recovery boiler 22, where heat is recovered and steam is generated.

[0035] The steam generated in the heat recovery boiler 22 is sent from a steam inlet 33 to a steam turbine 29 of the steam turbine facility 23, where it is expanded to drive the steam turbine 29, which then operates the generator 30. The exhaust steam from the steam turbine 29 is sent to a condenser 31 where it is condensed, and the condensed water produced by the condenser 31 is supplied to the heat recovery boiler 22.

[0036] Gas turbine equipment 21 (a generator 28 operated by driving an expansion turbine 27) and steam turbine equipment 23 (a generator 30 operated by driving a steam turbine 29) are connected to the power system 1. Meanwhile, renewable energy power generation equipment 11 that obtains electricity from renewable energy (wind power, solar power, etc.) is also connected to the power system 1.

[0037] The load of the power system 1 is covered by the electric power obtained by the gas turbine equipment 21, the steam turbine equipment 23, and the electric power obtained by the renewable energy power generation equipment 11.

[0038] The surplus of the electricity generated by the renewable energy power generation facility 11 and supplied to the power grid 1 is The system is provided with steam generating means 35 (fluid generating means: electric heater, heat pump, etc.) that generates steam as a fluid using the resulting surplus power.

[0039] The steam generated by the steam generating means 35 can be sent to the steam turbine 29 via the switching means 36. By supplying steam from the steam generating means 35 to the steam turbine 29 via the switching means 36, the steam turbine 29 can be driven by surplus electricity from the electricity obtained by the renewable energy power generation facility 11.

[0040] The energy of the steam turbine 29 driven by the surplus electricity is used to adjust the supply and demand of electricity by increasing or decreasing the output, to maintain the inertial force of rotating bodies such as the steam turbine 29 and the generator 30 within the power system, and to supply reactive power to the power system 1 using the generator 30, thereby providing parallel operation that maintains a state where there is no output at the sending end.

[0041] The output of the steam turbine 29 is increased or decreased by adjusting the output through open / close control (partially closed operation, throttling operation, etc.) of the steam passage of the steam supplied to the steam turbine 29. In addition, the output of the steam turbine 29 is increased or decreased by controlling the output of the electric heater, heat pump, etc. of the steam generating means 35 to adjust (store) the pressure of the steam supplied to the steam turbine 29.

[0042] Furthermore, it is also possible to use surplus electricity from the renewable energy power generation facility 11 to heat the stored fluid to obtain a high-temperature, high-pressure fluid (fluid generating means), expand the obtained high-temperature, high-pressure fluid in the expansion turbine 27, and drive the expansion turbine 27 using the surplus electricity.

[0043] The power generation system configured as described above can perform parallel operation in which excess power generated by the renewable energy power generation facility 11 and supplied to the power grid 1 is used to generate steam to drive the steam turbine 29, thereby maintaining a state in which there is no sending-end output. In other words, parallel operation can be performed regardless of the power generated by the gas turbine facility 21 and the steam turbine facility 23.

[0044] Therefore, in the combined power generation facility, there is no need to operate the gas turbine facility 21 (without using fuel such as natural gas) for operations to cover adjustment power, such as adjusting the supply and demand of electricity by increasing or decreasing the output, maintaining the inertial force of rotating bodies such as the steam turbine 29 and the generator 30 within the power system, and operating the generator 30 to supply reactive power to the power system 1, and it becomes possible to carry out operations to cover adjustment power (operation while maintaining a parallel state) with zero emissions.

[0045] Therefore, in the power generation system described above, it becomes possible to effectively utilize the surplus power generated by the renewable energy power generation facility 11 without storing the surplus power.

[0046] A third embodiment of the present invention will be described with reference to FIG.

[0047] Fig. 3 shows a schematic system for explaining the overall configuration of a power generation system according to a third embodiment of the present invention. Note that the same members as those shown in Figs. 1 and 2 are given the same reference numerals and their explanations are omitted.

[0048] The power generation system shown in Fig. 3 is an example of a system in which an industrial facility (for example, a factory) is equipped with an expansion turbine (steam turbine, gas turbine) that generates power to obtain a power source and heat source used in the factory. Alternatively, it is an example of a system of a joint thermal power generation facility that supplies electricity to industrial facilities (for example, a factory).

[0049] A factory 41, which is an industrial facility, is equipped with a gas turbine facility 42 and a steam turbine facility 43. Alternatively, electricity and heat (steam) are supplied from the gas turbine facility 42 and the steam turbine facility 43 of a joint thermal power plant.

[0050] High-temperature, high-pressure gas is supplied to the gas turbine equipment 42, which is expanded and driven by the expansion turbine 44, thereby generating electric power. Steam is supplied to the steam turbine equipment 43 from a boiler or the like, which is expanded and driven by the steam turbine 45, thereby generating electric power. The generated electric power is sent to the factory 41 to cover the factory's 41 electricity needs. In addition, heat extracted from the expansion turbine 44 and steam turbine 45 is sent to the factory 41 to cover the heat used in the factory 41.

[0051] Meanwhile, a renewable energy power generation facility 11 that obtains power from renewable energy (wind power, solar power, etc.) is connected to the power grid 1. Power is supplied from the power grid 1 to a factory 41, and part of the power used in the factory 41 is covered.

[0052] The system is equipped with a fluid generating means 46 (fluid generating means: electric heater, heat pump, etc.) that generates high-temperature, high-pressure fluid and / or steam using surplus electricity generated by the renewable energy power generation facility 11 and supplied to the power grid 1.

[0053] When the factory 41 is shut down for an extended period of time, such as for a holiday, there is almost no demand for electricity and heat, so the supply of high-temperature, high-pressure gas and steam from the boiler is stopped, and the gas turbine equipment 42 and steam turbine equipment 43 are shut down.

[0054] When the gas turbine equipment 42 and the steam turbine equipment 43 are stopped, the high-temperature, high-pressure fluid generated by the fluid generating means 46 is sent to the expansion turbine 44, and the steam generated by the fluid generating means 46 is sent to the steam turbine 45. By supplying the high-temperature, high-pressure fluid and steam from the fluid generating means 46 to the gas turbine equipment 42 and the steam turbine equipment 43, the expansion turbine 44 and the steam turbine 45 can be driven by surplus electricity obtained from the renewable energy power generation equipment 11.

[0055] The energy of the expansion turbine 44 and steam turbine 45 driven by surplus electricity is used to adjust the supply and demand of electricity by increasing or decreasing the output, maintain the inertial force of the rotating body within the power system, supply reactive power to the factory 41 and the power system 1, and maintain the continuous supply of heat (steam) to the factory 41. Parallel operation is performed to maintain a state where there is no output at the sending end.

[0056] The output of the expansion turbine 44 is increased or decreased by adjusting the output, for example, by controlling the opening and closing (partially closing operation, throttling operation, etc.) of the flow passage of the high-temperature, high-pressure fluid supplied to the expansion turbine 44. Also, the output of the electric heater, heat pump, etc. of the fluid generating means 46 is controlled to adjust (store) the pressure of the high-temperature, high-pressure fluid supplied to the expansion turbine 44.

[0057] The output of the steam turbine 45 is increased or decreased by adjusting the output through open / close control (partially closed operation, throttling operation, etc.) of the steam passage of the steam supplied to the steam turbine 45. Also, the output of the electric heater, heat pump, etc. of the fluid generating means 46 is controlled to adjust (store) the pressure of the steam supplied to the steam turbine 45.

[0058] The power generation system configured as described above can perform parallel operation in which surplus power generated by the renewable energy power generation facility 11 and supplied to the power grid 1 is used to generate high-temperature, high-pressure fluid and steam to drive the expansion turbine 44 and the steam turbine 45, thereby maintaining a state where there is no sending-end output. In other words, parallel operation can be performed without relying on power generated by normal operation of the gas turbine facility 42 and the steam turbine facility 43.

[0059] Therefore, with regard to operations to cover adjustment capacity, such as adjusting power supply and demand by increasing or decreasing output, maintaining the inertial force of rotating bodies within the power system, operations to supply reactive power to factories 41 and the power system 1, and parallel operation to maintain a state where there is no sending end output, there is no need to operate the gas turbine equipment 42 and steam turbine equipment 43 during normal operation (without using fuel such as natural gas), and it becomes possible to carry out operations to cover adjustment capacity (operations maintaining a parallel state) with zero emissions.

[0060] Therefore, in the above-described power generation system, when the industrial equipment (factory) is stopped, the parallel operation of the expansion turbines that generate electricity and heat (steam) can be covered by the surplus electricity, and while maintaining the inertial force of the expansion turbine 44 and the steam turbine 45, the surplus electricity generated by the renewable energy power generation equipment 11 can be effectively utilized without having to be stored.

[0061] Furthermore, even when the factory 41 is in operation, if the electricity required is supplied by relatively inexpensive electricity, it becomes possible to operate the expansion turbine 44 and the steam turbine 45 in parallel to obtain only heat (steam) without using fossil fuels (by reducing the amount of fossil fuels used), using surplus electricity from the electricity obtained by the renewable energy power generation facility 11. In other words, even when the factory 41 is in operation, it becomes possible to obtain heat (steam) using surplus electricity from the electricity obtained by the renewable energy power generation facility 11, while continuing to maintain the inertial force of the expansion turbine 44 and the steam turbine 45. [Industrial Applicability]

[0062] The present invention can be used in the industrial field of power generation systems that can effectively utilize surplus power. [Explanation of symbols]

[0063] 1 Power system 2, 29, 45 Steam turbines 3, 28, 30 Generator 4. Thermal power generation facilities 5 Combustion chamber 6. Boiler 7, 33 Steam inlet 11 Renewable energy power generation facilities 12, 35 Steam generating means 13, 36 Switching means 21, 42 Gas turbine equipment 22 Waste heat recovery boiler 23, 43 Steam turbine equipment 25 Compressor 26 Combustor 27, 44 Expansion turbine 31 Condenser 41 Factory 46 Fluid generating means

Claims

1. an expansion turbine that is driven by the expansion of a fluid to generate power; A renewable energy power generation facility connected to the power grid; a fluid generating means for generating a fluid for driving the expansion turbine using surplus electricity obtained from the renewable energy power generation facility, The expansion turbine is driven by the fluid generated by the fluid generating means, At least the inertial force of the generator and the expansion turbine is maintained in the power system, thereby performing parallel operation to maintain a state in which there is no power output at the sending end. A power generation system characterized by:

2. In the power generation system described in claim 1, The expansion turbine is A steam turbine is supplied with steam generated in a boiler that burns fuel to produce steam. A power generation system characterized by:

3. In the power generation system described in claim 1, The expansion turbine is This is a steam turbine that is supplied with steam generated in a heat recovery boiler that obtains steam from the exhaust gas of a gas turbine. A power generation system characterized by:

4. In the power generation system described in claim 1, The expansion turbine is It is an expansion turbine that generates power to generate electricity and heat for use in industrial facilities. A power generation system characterized by:

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