High-temperature heat storage type power generation peak regulation and frequency modulation system

Abstract

The utility model provides a high-temperature heat storage type power generation peak and frequency modulation system, which relates to the technical field of thermoelectricity and comprises a power generation system, a first heat storage and exchange system and a second heat storage and exchange system. The power generation system comprises a generator, a water supply device, a steam generator, a superheater, a turbine and a condenser, the first heat storage and exchange system comprises a first electric heater, a first heat storage device, a first circulating fan and a first gas circulating pipeline; the second heat storage and exchange system comprises a second electric heater, a second heat storage device, a second circulating fan and a second gas circulating pipeline; according to the utility model, abundant electric energy can be converted into heat energy to be stored, and when frequency modulation and peak regulation are needed, the stored heat energy is utilized to drive the steam turbine set to generate electricity, so that rotation inertia and primary frequency modulation capability are provided for a power grid, and peak load shifting is realized.

Description

Technical Field

[0001] This utility model relates to the field of thermoelectric technology, and in particular to a high-temperature thermal storage power generation peak shaving and frequency regulation system. Background Technology

[0002] Large-scale grid connection of renewable energy sources such as wind and solar power is an important path to achieving the "dual carbon" target. However, the inherent intermittency and volatility of renewable energy sources pose significant challenges to the real-time balance of the power grid, leading to an increasing demand for peak shaving and frequency regulation. This places higher demands on both the "quality" and "quantity" of the grid's flexible regulation capabilities. Therefore, it is necessary to design a peak shaving and frequency regulation system to provide the power grid with primary frequency regulation capabilities, better achieve peak shaving and valley filling, and improve energy efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a high-temperature thermal energy storage power generation peak shaving and frequency regulation system to solve the problems existing in the prior art. It can convert surplus electrical energy into thermal energy for storage, and when frequency regulation and peak shaving are required, it can use the stored thermal energy to drive the steam turbine unit to generate electricity, providing the power grid with rotational inertia and primary frequency regulation capability, thereby realizing peak shaving and valley filling.

[0004] To achieve the above objectives, this utility model provides the following solution:

[0005] A high-temperature thermal energy storage power generation peak-shaving and frequency regulation system includes a power generation system, a first thermal energy storage and heat exchange system, and a second thermal energy storage and heat exchange system. The power generation system includes a generator and, in sequence, a water supply device, a steam generator, a superheater, a steam turbine, and a condenser. The power output terminal of the steam turbine is connected to the power input terminal of the generator, and the power output terminal of the generator is connected to a high-voltage power grid. The water supply device supplies water to the steam generator, which generates saturated steam. The superheater heats the saturated steam into superheated steam. The steam turbine uses the superheated steam to drive the generator to generate electricity. The condenser condenses the steam discharged from the steam turbine. The first thermal energy storage and heat exchange system includes a first electric heater, a first thermal energy storage device, a first circulating fan, and a first gas circulation pipeline. An electric heater is connected to the power distribution network and is used to heat the first thermal storage device. The first thermal storage device, the first circulating fan, and the steam generator are all installed on the first gas circulation pipeline. The gas in the first gas circulation pipeline is heated by the first thermal storage device and then exchanges heat with the water in the steam generator. The second thermal storage and heat exchange system includes a second electric heater, a second thermal storage device, a second circulating fan, and a second gas circulation pipeline. The second electric heater is connected to the power distribution network and is used to heat the second thermal storage device. The second thermal storage device, the second circulating fan, and the superheater are all installed on the second gas circulation pipeline. The gas in the second gas circulation pipeline is heated by the second thermal storage device and then exchanges heat with the steam in the superheater.

[0006] In one embodiment, both the first heat storage device and the second heat storage device are made of heat storage material, and both the first heat storage device and the second heat storage device are provided with heat extraction channels, which are connected to the first gas circulation pipeline or the second gas circulation pipeline.

[0007] In one embodiment, the first electric heater and the second electric heater are both electromagnetic induction heaters correspondingly installed in the first heat storage device and the second heat storage device.

[0008] In one embodiment, both the first heat storage device and the second heat storage device are made of iron.

[0009] As one embodiment, a desuperheater for controlling the turbine intake temperature is also provided between the superheater and the turbine.

[0010] As one embodiment, the water supply device includes a water tank for supplying water to the steam generator.

[0011] As one embodiment, a water pump is provided at the drain outlet of the condenser, and the outlet of the water pump is connected to the steam generator and / or the water tank.

[0012] As one implementation, the generator is connected to the high-voltage power grid via a transformer.

[0013] In one embodiment, the power distribution network is connected to the first thermal storage device and the second thermal storage device through the electric heating temperature controller.

[0014] As one embodiment, both the first gas circulation pipeline and the second gas circulation pipeline are filled with inert gas.

[0015] This utility model has the following technical advantages over the prior art:

[0016] This invention, by setting up a first thermal energy storage and heat exchange system and a second thermal energy storage and heat exchange system, can convert surplus electrical energy into thermal energy and store it in the first and second thermal energy storage devices. When peak shaving and frequency regulation are required, the thermal energy in the first and second thermal energy storage devices is used to heat the subcooled water entering the steam heat exchanger and the saturated steam entering the superheater, respectively. The resulting superheated steam drives the steam turbine to do work and drives the generator to generate electricity, providing the power grid with rotational inertia and primary frequency regulation capability, thus achieving peak shaving and valley filling. It can be widely used in the field of power system peak shaving and frequency regulation, such as new energy power plants and flexible retrofitting of thermal power plants. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a high-temperature thermal storage power generation peak-shaving and frequency regulation system in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of the first heat storage device and the second heat storage device in one embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures:

[0021] 1. Water tank; 2. Steam generator; 3. Superheater; 4. Desuperheater; 5. Steam turbine; 6. Generator; 7. Condenser; 8. First heat storage device; 9. Second heat storage device; 10. First circulating fan; 11. Second circulating fan; 12. Water pump; 13. Heat extraction channel; 14. Heat storage channel; 15. Electric heating temperature controller; 16. Transformer. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] The purpose of this invention is to provide a high-temperature thermal energy storage power generation peak shaving and frequency regulation system to solve the problems existing in the prior art. It can convert surplus electrical energy into thermal energy for storage, and when frequency regulation and peak shaving are required, it can use the stored thermal energy to drive the steam turbine unit to generate electricity, providing the power grid with rotational inertia and primary frequency regulation capability, thereby realizing peak shaving and valley filling.

[0024] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] like Figure 1 As shown in the figure, this embodiment provides a high-temperature thermal storage power generation peak shaving and frequency regulation system, including a power generation system, a first thermal storage and heat exchange system and a second thermal storage and heat exchange system.

[0026] The main function of the power generation system is to complete the steam-water cycle and use the steam to drive the turbine 5 to generate electricity and connect it to the grid. Specifically, the power generation system includes a generator 6 and a water supply device, a steam generator 2, a superheater 3, a turbine 5, and a condenser 7 connected in sequence. The power output end of the turbine 5 is connected to the power input end of the generator 6, and the power output end of the generator 6 is connected to the high-voltage power grid. The water supply device is used to provide a stable water source to the steam generator 2 during the peak-shaving and frequency regulation system startup time. To ensure water quality and temperature, the water supply device includes a water treatment unit (e.g., a filter membrane device) and a temperature control unit (e.g., a water temperature controller). The filter membrane device and the water temperature controller are commonly used devices in this field, and their specific structures will not be described in detail in this embodiment. The steam generator 2 is a saturated boiler used to convert superheated water into saturated steam. After saturated steam flows into superheater 3, it is further heated, becoming high-temperature, high-pressure superheated steam, which then flows into turbine 5, driving turbine 5 to perform work. Simultaneously, turbine 5 drives generator 6 to generate electricity, which is then fed into the high-voltage power grid via transformer 16. The steam discharged from turbine 5 enters condenser 7, where it is completely condensed. The condensate can be used by steam generator 2 or for other applications.

[0027] Both the first and second thermal energy storage systems are used to convert surplus electrical energy into thermal energy for storage. During peak-shaving and frequency regulation, this thermal energy is released to drive the steam turbine 5 to generate electricity. Specifically, the first thermal energy storage system includes a first electric heater, a first thermal energy storage device 8, a first circulating fan 10, and a first gas circulation pipeline. The first electric heater is connected to the power distribution network and is used to heat the first thermal energy storage device 8 for thermal energy storage. The first thermal energy storage device 8, the first circulating fan 10, and the steam generator 2 are all located on the first gas circulation pipeline. When the gas in the first gas circulation pipeline flows through the first thermal energy storage device 8, it absorbs heat from the device. The heated gas then exchanges heat with the subcooled water in the steam generator 2, heating the subcooled water into saturated steam.

[0028] The second thermal storage and heat exchange system includes a second electric heater, a second thermal storage device 9, a second circulating fan 11, and a second gas circulation pipeline. The second electric heater is connected to the power distribution network and is used to heat the second thermal storage device 9 for thermal storage. The second thermal storage device 9, the second circulating fan 11, and the steam generator 2 are all installed on the second gas circulation pipeline. When the gas in the second gas circulation pipeline flows through the second thermal storage device 9, it acquires heat from the second thermal storage device 9. The gas that has acquired heat then exchanges heat with the saturated steam in the superheater 3, heating the saturated steam into superheated steam.

[0029] Therefore, this embodiment, by setting up a first thermal energy storage and heat exchange system and a second thermal energy storage and heat exchange system, can convert surplus electrical energy (such as excess electrical energy generated at night) into thermal energy and store it in the first thermal energy storage device 8 and the second thermal energy storage device 9. When peak shaving and frequency regulation are required (such as when electricity consumption is high during the day), the thermal energy in the first thermal energy storage device 8 and the thermal energy in the second thermal energy storage device 9 are used to heat the subcooled water entering the steam heat exchanger and the saturated steam entering the superheater 3, respectively. Finally, the superheated steam drives the steam turbine 5 to do work and drives the generator 6 to generate electricity, providing the power grid with rotational inertia and primary frequency regulation capability, realizing peak shaving and valley filling. It can be widely used in the field of power system peak shaving and frequency regulation, such as new energy power plants and flexible transformation of thermal power plants.

[0030] It should be noted that the heat required to heat subcooled water into saturated steam is greater than the heat required to heat saturated steam into superheated steam. Therefore, during the design phase, the heat storage design of the first heat storage device 8, the selection of the first circulating fan 10, and the size of the first gas circulation pipeline all need to be reasonably selected based on the actual application environment.

[0031] As one implementation, in this embodiment, the first and second thermal storage heat exchange systems are basically the same except for the heating object of the heat-extracting gas. Both the first thermal storage device 8 and the second thermal storage device 9 are made of thermal storage material. In this embodiment, the thermal conductivity of the thermal storage material of the first thermal storage device 8 and the second thermal storage device 9 is greater than 50 W / (m·K). High thermal conductivity can enhance the heat transfer effect, accelerate the heat storage and release rate, shorten the start-up time of the steam turbine 5, and improve energy utilization. The first thermal storage device 8 and the second thermal storage device 9 have a high temperature resistance of not less than 800℃ and can provide industrial high-temperature steam of not less than 400℃~500℃. Specifically, in this embodiment, both the first thermal storage device 8 and the second thermal storage device 9 are made of iron. Structurally, both the first thermal storage device 8 and the second thermal storage device 9 are provided with heat extraction channels 13, such as... Figure 2 As shown; the heat extraction channel 13 is connected to either the first gas circulation pipeline or the second gas circulation pipeline. The heat extraction channel 13 is used to circulate heat exchange gas, allowing the gas to acquire the heat stored in the first heat storage device 8 and the second heat storage device 9.

[0032] In this embodiment, the gases in the first gas circulation pipeline and the second gas circulation pipeline are both inert gases.

[0033] In one embodiment, both the first electric heater and the second electric heater are electromagnetic induction heaters correspondingly installed within the first heat storage device 8 and the second heat storage device 9. Specifically, both the first heat storage device 8 and the second heat storage device 9 are provided with heat storage channels 14, such as... Figure 2 As shown, the electromagnetic induction heater is embedded in the heat storage channel 14 and heats the first heat storage device 8 and the second heat storage device 9 through the principle of electromagnetic induction to store thermal energy.

[0034] As one implementation, a desuperheater 4 is also provided between the superheater 3 and the turbine 5 to control the intake temperature of the turbine 5, ensuring that the temperature of the superheated steam flowing into the turbine 5 meets the requirements.

[0035] In one embodiment, the water supply device includes a water tank 1 for supplying water to the steam generator 2. The water tank 1 is positioned higher than the steam generator 2 and is used to replenish water to the steam generator 2. A water pump 12 is installed at the drain outlet of the condenser 7. The outlet of the water pump 12 is connected to the steam generator 2 and / or the water tank 1, and can discharge condensate into the water tank 1 for storage, or directly supply condensate into the steam generator 2 for replenishment.

[0036] As one implementation, the power distribution network is connected to the first thermal storage device 8 and the second thermal storage device 9 through an electric heating temperature controller 15. The electric heating temperature controller 15 can control the magnitude of the output energy storage heating current based on the temperature feedback of the first thermal storage device 8 and the second thermal storage device 9.

[0037] Any adaptive changes made according to actual needs are within the protection scope of this utility model.

[0038] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A high-temperature thermal storage power generation peak-shaving and frequency regulation system, characterized in that, include: A power generation system includes a generator and, in sequence, a water supply device, a steam generator, a superheater, a steam turbine, and a condenser. The power output terminal of the steam turbine is connected to the power input terminal of the generator, and the power output terminal of the generator is connected to a high-voltage power grid. The water supply device supplies water to the steam generator, which generates saturated steam. The superheater heats the saturated steam into superheated steam. The steam turbine uses the superheated steam to drive the generator to generate electricity. The condenser condenses the steam discharged from the steam turbine. The first thermal energy storage and heat exchange system includes a first electric heater, a first thermal energy storage device, a first circulating fan, and a first gas circulation pipeline. The first electric heater is connected to the power distribution network and is used to heat the first thermal energy storage device. The first thermal energy storage device, the first circulating fan, and the steam generator are all installed on the first gas circulation pipeline. The gas in the first gas circulation pipeline is heated by the first thermal energy storage device and then exchanges heat with the water in the steam generator. The system includes a second thermal storage and heat exchange system, comprising a second electric heater, a second thermal storage device, a second circulating fan, and a second gas circulation pipeline. The second electric heater is connected to the power distribution network and is used to heat the second thermal storage device. The second thermal storage device, the second circulating fan, and the superheater are all installed on the second gas circulation pipeline. The gas in the second gas circulation pipeline is heated by the second thermal storage device and then exchanges heat with the steam in the superheater.

2. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, Both the first and second heat storage devices are made of heat storage materials. Both the first and second heat storage devices are provided with heat extraction channels, which are connected to the first or the second gas circulation pipeline.

3. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 2, characterized in that, Both the first electric heater and the second electric heater are electromagnetic induction heaters correspondingly installed in the first heat storage device and the second heat storage device.

4. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 3, characterized in that, Both the first and second thermal storage devices are made of iron.

5. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, A desuperheater for controlling the turbine intake air temperature is also provided between the superheater and the turbine.

6. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, The water supply device includes a water tank for supplying water to the steam generator.

7. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 6, characterized in that, A water pump is installed at the drain outlet of the condenser, and the outlet of the water pump is connected to the steam generator and / or the water tank.

8. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, The generator is connected to the high-voltage power grid via a transformer.

9. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, The power distribution network is connected to the first thermal storage device and the second thermal storage device through an electric heating temperature controller.

10. The high-temperature thermal storage power generation peak-shaving and frequency regulation system according to claim 1, characterized in that, Both the first gas circulation pipeline and the second gas circulation pipeline are filled with inert gas.

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