Nuclear power-thermal power coupling system for improving thermal energy grade and realizing flexible and rapid peak regulation

Abstract

The present application relates to the technical field of power grid peak shaving and comprehensive energy utilization, in particular to a thermal and nuclear power coupling system for improving thermal energy grade and realizing flexible and rapid peak shaving. The system comprises a nuclear power unit, a thermal power unit, a heat pump unit and a heat storage unit. The nuclear power unit outputs a heat source carrying heat. The thermal power unit is connected with the nuclear power unit in pipeline and receives at least part of the heat source output by the nuclear power unit for heat preservation. The heat pump unit is connected with the nuclear power unit in pipeline and receives another part of the heat source output by the nuclear power unit and improves the heat grade of the heat source. The heat storage unit is connected with the heat pump unit in heat exchange and receives and stores the heat from the heat pump unit. The heat storage unit is connected with the thermal power unit in pipeline and releases heat to the thermal power unit for power generation. The system can realize rapid and flexible peak shaving and improve the utilization grade of redundant thermal energy of nuclear power without frequent adjustment of the power of nuclear reactor.

Description

Technical Field

[0001] This invention relates to the field of power grid peak shaving and integrated energy utilization technology, specifically to a thermal power-nuclear power coupling system that improves thermal energy quality and achieves flexible and rapid peak shaving. Background Technology

[0002] With the increasing difference between peak and valley power loads, the power grid is placing higher demands on the deep peak-shaving capabilities of generating units. As important power sources in the power grid, the operational flexibility of thermal power units and nuclear power units directly affects the safe and stable operation of the power grid.

[0003] To cope with peak-valley variations in electricity load, existing thermal power units often employ a deep peak-shaving scheme, shutting down during off-peak hours and operating during peak hours. However, after shutdown, the core equipment within a thermal power unit, such as the boiler and turbine, gradually cools naturally to room temperature. When the unit receives a grid connection command again during peak hours, it must perform a cold start operation. The cold start process of a thermal power unit involves the slow heating of water and metal components, which is extremely time-consuming. This long start-up process severely restricts the unit's response speed and flexibility to grid peak-shaving commands.

[0004] On the other hand, nuclear power units are constrained by the physical characteristics of nuclear reactors and strict safety operation requirements. During operation, they should not frequently and significantly adjust the heat load of the reactor heat source. As a result, when traditional single nuclear power units face the peak-shaving demand of large-scale peak-valley differences in new power systems, it is difficult to directly adjust the underlying heat source to achieve rapid power increase or decrease. Summary of the Invention

[0005] To address the above problems, this invention provides a thermal power-nuclear power coupling system that improves thermal energy quality and enables flexible and rapid peak shaving. It can achieve rapid and flexible peak shaving and improve the utilization quality of redundant nuclear thermal energy without frequently adjusting the power of the nuclear power reactor.

[0006] This invention provides a thermal power-nuclear power coupling system that improves the quality of thermal energy and enables flexible and rapid peak shaving. The system includes a nuclear power unit, a thermal power unit, a heat pump unit, and a thermal storage unit. The nuclear power unit outputs a heat source carrying heat. The thermal power unit is connected to the nuclear power unit via pipelines and receives at least a portion of the heat source output by the nuclear power unit for insulation. The heat pump unit is connected to the nuclear power unit via pipelines and receives another portion of the heat source output by the nuclear power unit, improving the heat quality of the heat source. The thermal storage unit is connected to the heat pump unit via heat exchange, receiving and storing heat from the heat pump unit. Furthermore, the thermal storage unit is connected to the thermal power unit via pipelines and releases heat to the thermal power unit to generate electricity.

[0007] Optionally, the nuclear power unit includes a nuclear reactor, a nuclear steam generator connected to the nuclear reactor for heat exchange to form a heat source, a nuclear steam turbine whose heat source inlet is connected to the heat source outlet of the nuclear steam generator, a nuclear condenser whose heat source inlet is connected to the heat source outlet of the nuclear steam turbine, and a nuclear circulating pump whose heat source inlet is connected to the heat source outlet of the nuclear condenser and whose heat source outlet is connected to the heat source inlet of the nuclear steam generator.

[0008] Optionally, the thermal power unit includes a thermal power boiler, a thermal power turbine high-pressure cylinder whose heat source inlet is connected to the heat source outlet of the thermal power boiler, a thermal power reheater whose heat source inlet is connected to the heat source outlet of the thermal power turbine high-pressure cylinder, a thermal power turbine intermediate-pressure cylinder whose heat source inlet is connected to the heat source outlet of the thermal power reheater, and a thermal power turbine low-pressure cylinder whose heat source inlet is connected to the heat source outlet of the thermal power turbine intermediate-pressure cylinder and whose heat source outlet is connected to the heat source inlet of the nuclear power unit.

[0009] Optionally, the heat pump internally circulates a heat pump working fluid. The heat pump unit includes a first heat exchanger, a heat pump compressor, a second heat exchanger, and a heat pump depressurization device. The heat source inlet of the first heat exchanger is connected to the heat source outlet of the nuclear power steam generator, and the heat source outlet is connected to the heat source inlet of the nuclear power steam generator. The heat source entering the first heat exchanger exchanges heat with the heat pump working fluid. The heat pump compressor's working fluid inlet is connected to the heat pump working fluid outlet of the first heat exchanger. The heat pump second heat exchanger's working fluid inlet is connected to the heat pump compressor's working fluid outlet. The heat pump depressurization device's working fluid inlet is connected to the heat pump second heat exchanger's working fluid outlet.

[0010] Optionally, the heat storage unit circulates a heat storage medium internally. The heat storage unit includes a cryogenic storage tank, a high-temperature storage tank, and a heat storage medium heat exchange device. The heat storage medium outlet of the cryogenic storage tank is connected to the heat storage medium inlet of the second heat exchanger of the heat pump; the heat storage medium inlet of the high-temperature storage tank is connected to the heat storage medium outlet of the second heat exchanger of the heat pump; the heat storage medium inlet of the heat storage medium heat exchange device is connected to the heat storage medium outlet of the high-temperature storage tank, and the heat storage medium outlet of the heat storage medium heat exchange device is connected to the heat storage medium inlet of the cryogenic storage tank.

[0011] Optionally, the thermal power unit circulates a thermal power working fluid, and the thermal power unit also includes a thermal power condenser and a thermal power circulating pump; the thermal power working fluid outlet of the thermal power condenser is connected to the thermal power working fluid inlet of the heat storage medium heat exchange device, and the thermal power working fluid outlet of the heat storage medium heat exchange device is connected to the thermal power boiler and the thermal power working fluid inlet of the high-pressure cylinder of the thermal power turbine, respectively; the heat storage medium in the heat storage medium heat exchange device exchanges heat with the thermal power working fluid from the thermal power condenser; the thermal power circulating pump is connected to the pipeline between the thermal power condenser and the thermal power boiler and between the thermal power condenser and the heat storage medium heat exchange device.

[0012] Optionally, the thermal power unit also includes an insulated inlet pipe and an insulated return pipe; the heat source inlet of the insulated inlet pipe is connected to the heat source outlet of the nuclear power steam generator, and its heat source outlet is connected to the heat source inlet of the thermal power boiler; the heat source inlet of the insulated return pipe is connected to the pipe section between the heat source outlet of the low-pressure cylinder of the thermal power turbine and the heat source inlet of the thermal power condenser, and its heat source outlet is connected to the heat source inlet of the nuclear power turbine.

[0013] Optionally, the coupling system also includes a regulating control unit; the regulating control unit is connected to the nuclear power unit, thermal power unit, heat pump unit and thermal storage unit respectively, and is configured to switch and adjust the valve opening on each pipeline according to the grid load status, so as to control the flow state of the heat source, heat pump working fluid, thermal storage medium and thermal power working fluid.

[0014] Optionally, the system control logic of the adjustment control unit is configured as follows: Receive grid peak shaving commands and determine grid load status; When the grid load is determined to be during off-peak hours, the heat source output from the nuclear power unit is controlled to reduce the amount of electricity fed into the grid; at least part of the heat source is connected to the thermal power unit that is in a shutdown state for insulation; another part of the heat source is input to the heat pump unit, the heat pump unit is controlled to improve the heat quality of the heat source, and the heat from the heat pump unit is received and stored by the heat storage unit. When the grid load is determined to be during peak power, the thermal power unit is controlled to receive the grid connection command and start ignition; the thermal power unit is controlled to perform hot start or warm start by utilizing the insulation during off-peak power; and the thermal storage unit is controlled to release heat to the thermal power unit to generate electricity.

[0015] Optionally, the nuclear power unit includes at least one of the following: pressurized water reactor, boiling water reactor, heavy water reactor, high-temperature gas-cooled reactor, sodium-cooled fast reactor, molten salt reactor power generation or heating system; the energy conversion cycle of the thermal power unit includes at least one of the following: steam Rankine cycle, reheat Rankine cycle, gas-steam combined cycle, organic Rankine cycle, supercritical carbon dioxide cycle, combined heat and power cycle, or combination of the above cycles; the heat pump working fluid circulating in the heat pump unit includes one or more combinations of air, helium, argon, or carbon dioxide; and the heat storage medium flowing in the heat storage unit includes molten salt or inert particles.

[0016] The thermal power-nuclear power coupling system provided by this invention, which enhances the quality of thermal energy and enables flexible and rapid peak shaving, deeply couples thermal power units with nuclear power units, heat pump units, and thermal storage units. During off-peak hours, the thermal power units receive heat from the nuclear power units for equipment insulation, avoiding shutdown and cooling of the thermal power units and laying a warm or hot foundation for subsequent rapid startup. Simultaneously, the heat pump units absorb another portion of the heat from the nuclear power units, enhance the heat quality, and store it in the thermal storage unit, achieving efficient conversion and storage of redundant low-grade thermal energy from nuclear power during off-peak hours. During peak hours, the thermal storage unit releases high-grade heat to the thermal power units to generate electricity. This not only promptly compensates for the power shortage during the initial startup and ramp-up phase of the thermal power units, shortening grid connection response time, but also adds power generation during normal operation of the thermal power units. Thus, without frequent power adjustments by the nuclear reactor, it greatly improves the rapid and flexible peak shaving capability of the power plant-level grid and the overall quality of energy utilization. Attached Figure Description

[0017] Figure 1 This is a block diagram of the overall structure of a thermal power-nuclear power coupling system that improves thermal energy quality and achieves flexible and rapid peak shaving, provided by an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the equipment structure of a thermal power-nuclear power coupling system that improves thermal energy quality and achieves flexible and rapid peak shaving, provided by an embodiment of the present invention.

[0019] Figure 3 A control flowchart for a thermal power-nuclear power coupling system that improves thermal energy quality and achieves flexible and rapid peak shaving, provided for embodiments of the present invention.

[0020] Figure reference numerals: 100A - Coupling system of thermal power and nuclear power; 100 - Nuclear power unit; 200 - Thermal power unit; 300 - Heat pump unit; 400 - Thermal storage unit; S10 - First extraction steam; S11 - Thermal power return steam; S20 - Second extraction steam; S21 - Heat pump return steam; S30 - Thermal power working fluid; S31 - Additional steam generated by the thermal storage system; H1 - Heat pump heating; 1 - Nuclear reactor; 2 - Nuclear steam generator; 3 - Nuclear turbine; 4 5-Nuclear power condenser; 6-Nuclear power circulating pump; 7-Thermal power boiler; 8-Thermal power turbine high-pressure cylinder; 9-Thermal power reheater; 10-Thermal power turbine intermediate-pressure cylinder; 11-Thermal power condenser; 12-Thermal power circulating pump; 13-Heat pump first heat exchanger; 14-Heat pump compressor; 15-Heat pump second heat exchanger; 16-Heat pump pressure reduction equipment; 17-Cryogenic storage tank; 18-High temperature storage tank; 19-Heat exchange equipment for thermal storage medium. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] This embodiment provides a thermal power-nuclear power coupling system 100A that improves thermal energy quality and enables flexible and rapid peak shaving. For example... Figure 1 As shown, the thermal power-nuclear power coupling system 100A mainly includes a nuclear power unit 100, a thermal power unit 200, a heat pump unit 300, and a thermal storage unit 400.

[0023] In existing generator unit operations, thermal power systems gradually cool down after shutdown during off-peak hours. When reconnection to the grid is required during peak hours, thermal power systems face slow cold starts, severely restricting the unit's response speed to grid peak-shaving commands. Meanwhile, nuclear power units, limited by reactor safety characteristics, find it difficult to frequently adjust heat source loads. Therefore, this embodiment deeply couples the nuclear power unit 100 and the thermal power unit 200.

[0024] In this embodiment, the nuclear power unit 100 operates continuously and outputs a heat source carrying heat. Specifically, the nuclear power unit 100 includes a nuclear power reactor 1, a nuclear power steam generator 2, a nuclear power steam turbine 3, a nuclear power condenser 4, and a nuclear power circulating pump 5. The nuclear power reactor 1 and the nuclear power steam generator 2 are connected for heat exchange to form a heat source. The heat source inlet of the nuclear power steam turbine 3 is connected to the heat source outlet pipe of the nuclear power steam generator 2. The heat source inlet of the nuclear power condenser 4 is connected to the heat source outlet pipe of the nuclear power steam turbine 3. The heat source inlet of the nuclear power circulating pump 5 is connected to the heat source outlet pipe of the nuclear power condenser 4, and its heat source outlet is connected to the heat source inlet pipe of the nuclear power steam generator 2, forming a circulation loop on the nuclear power side.

[0025] The thermal power unit 200 is connected to the nuclear power unit 100 by piping, and includes a thermal power boiler 6, a thermal power turbine high-pressure cylinder 7, a thermal power reheater 8, a thermal power turbine intermediate-pressure cylinder 9, a thermal power turbine low-pressure cylinder 10, a thermal power condenser 11, and a thermal power circulating pump 12. Specifically, refer to... Figure 1 and Figure 2The heat source inlet of the high-pressure cylinder 7 of the thermal power turbine is connected to the heat source outlet pipeline of the thermal power boiler 6. The heat source inlet of the thermal power reheater 8 is connected to the heat source outlet pipeline of the high-pressure cylinder 7 of the thermal power turbine. The heat source inlet of the intermediate-pressure cylinder 9 of the thermal power turbine is connected to the heat source outlet pipeline of the thermal power reheater 8. The heat source inlet of the low-pressure cylinder 10 of the thermal power turbine is connected to the heat source outlet pipeline of the intermediate-pressure cylinder 9 of the thermal power turbine, and its heat source outlet is connected to the heat source inlet of the nuclear power unit 100. During off-peak electricity periods, the thermal power unit 200 receives at least a portion of the heat source output from the nuclear power unit 100 through the above-mentioned pipeline connections for equipment insulation.

[0026] The heat pump unit 300 is connected to the nuclear power unit 100 via piping. The heat pump unit 300 contains a circulating heat pump working fluid, and its components include a first heat exchanger 13, a heat pump compressor 14, a second heat exchanger 15, and a heat pump depressurization device 16. Specifically, refer to... Figure 1 and Figure 2 The heat pump compressor 14's working fluid inlet is connected to the heat pump working fluid outlet pipe of the first heat exchanger 13; the heat pump second heat exchanger 15's working fluid inlet is connected to the heat pump compressor 14's working fluid outlet pipe; the heat pump depressurization device 16's working fluid inlet is connected to the heat pump second heat exchanger 15's working fluid outlet pipe; and the heat pump depressurization device 16's working fluid outlet is connected to the heat pump first heat exchanger 13's working fluid inlet pipe, thus forming an internal circulation loop for the heat pump working fluid. Simultaneously, the heat source inlet of the first heat exchanger 13 is connected to the heat source outlet pipe of the nuclear power steam generator 2, and its heat source outlet is connected to the heat source inlet pipe of the nuclear power steam generator 2. The heat pump unit 300 thus receives a portion of the heat source output from the nuclear power unit 100, such as the second extraction steam S20, which enters the heat source of the first heat exchanger 13 to exchange heat with the heat pump working fluid, and the heat pump compressor 14 increases the heat quality of the heat pump working fluid.

[0027] The heat storage unit 400 is connected to the heat pump unit 300 for heat exchange. The heat storage unit 400 internally circulates a heat storage medium and includes a low-temperature storage tank 17, a high-temperature storage tank 18, and a heat exchange device 19 for the heat storage medium. Specifically, refer to... Figure 1 and Figure 2 The outlet of the thermal storage medium in the low-temperature storage tank 17 is connected to the inlet pipe of the thermal storage medium in the second heat exchanger 15 of the heat pump; the inlet of the thermal storage medium in the high-temperature storage tank 18 is connected to the outlet pipe of the thermal storage medium in the second heat exchanger 15 of the heat pump; the inlet of the thermal storage medium heat exchange device 19 is connected to the outlet pipe of the thermal storage medium in the high-temperature storage tank 18, and its outlet is connected to the inlet pipe of the thermal storage medium in the low-temperature storage tank 17. Through the above connections, the thermal storage unit 400 receives heat from the heat pump unit 300 at the second heat exchanger 15 of the heat pump and stores the thermal storage medium that has absorbed high-grade heat in the high-temperature storage tank 18.

[0028] In this embodiment, the thermal storage unit 400 is connected to the thermal power unit 200 via piping. The thermal power unit 200 circulates a thermal power working fluid, and the thermal power working fluid outlet of the thermal power condenser 11 is connected to the thermal power working fluid inlet pipe of the thermal power storage medium heat exchange device 19. The thermal power working fluid outlet of the thermal power storage medium heat exchange device 19 is connected to the thermal power working fluid inlet pipe of the thermal power boiler 6 and the thermal power working fluid inlet pipe of the high-pressure cylinder 7 of the thermal power turbine, respectively. The thermal power circulation pump 12 is connected to the piping between the thermal power condenser 11 and the thermal power boiler 6, and between the thermal power condenser 11 and the thermal power storage medium heat exchange device 19, to drive the working fluid circulation. During peak power periods, the thermal power storage medium in the high-temperature storage tank 18 enters the thermal power storage medium heat exchange device 19, releasing heat to the thermal power working fluid S30 from the thermal power unit 200 to generate electricity.

[0029] It should be noted that the power generation system of nuclear power unit 100 can be a water-cooled reactor nuclear power system. It can also be at least one of the following: pressurized water reactor, boiling water reactor, heavy water reactor, high-temperature gas-cooled reactor, sodium-cooled fast reactor, or molten salt reactor power generation or heating system. The heat source carrying the output heat can be nuclear steam. It can also be a high-temperature liquid thermal medium safely isolated by an intermediate heat exchanger. The heat pump working fluid circulating in heat pump unit 300 can be air. It can also be a conventional gas working fluid such as helium, argon, or carbon dioxide, or a new type of heat pump working fluid suitable for a wide temperature range. The heat storage medium flowing in heat storage unit 400 can be molten salt. It can also be inert particles, etc. The above media have the advantages of high energy storage density and good high-temperature stability, which is suitable for increasing the heat grade from 300℃. + The thermal energy storage requirement is raised from 50°C to over 600°C. The energy conversion cycle of the thermal power unit 200 can be a steam Rankine cycle. It can also be at least one of a reheat Rankine cycle, a gas-steam combined cycle, an organic Rankine cycle, a supercritical carbon dioxide cycle, a combined heat and power cycle, or a combination of the above cycles. The working fluid S30 can be high-pressure feedwater. It can also be steam discharged from the high-pressure cylinder 7 of the thermal power turbine or other suitable working fluid.

[0030] In this embodiment, the thermal power-nuclear power coupling system 100A also includes a regulation and control unit (not shown in the figure). The regulation and control unit is signal-connected to the nuclear power unit, thermal power unit, heat pump unit, and thermal storage unit, respectively. It is configured to switch and adjust the valve openings on each pipeline according to the grid load status to control the flow state of the heat source, heat pump working fluid, thermal storage medium, and thermal power working fluid. Specifically, the regulation and control unit of the thermal power-nuclear power coupling system 100A receives grid peak-shaving commands and judges and switches the system's operating state. The system is configured to switch between energy storage and heat preservation mode during off-peak hours and energy release and power generation mode during peak hours according to the grid load status.

[0031] Specifically, the system control logic of the regulating control unit in this embodiment is configured as follows: receiving a grid peak-shaving command and determining the grid load status. When the grid load status is determined to be during off-peak hours, the regulating control unit controls the extraction of the heat source output by the nuclear power unit 100 to reduce the amount of electricity fed into the grid; wherein, at least part of the heat source, such as the first extraction steam S10, is connected to the thermal power unit 200 which is in a shutdown state to keep its interior warm; another part of the heat source, such as the second extraction steam S20, is input to the heat pump unit 300, controlling the heat pump unit 300 to consume electricity to do work to improve the heat quality of the heat source, and the heat storage unit 400 receives and stores the heat from the heat pump unit 300. When the grid load is determined to be during peak power, the regulating control unit controls the thermal power unit 200 to receive the grid connection command and ignite; controls the thermal power unit 200 to perform hot or warm start-up using the insulation base during off-peak power; simultaneously, controls the thermal storage unit 400 to release heat to the thermal power unit 200 to generate electricity, such as generating additional steam S31 produced by the thermal storage system; in combination with the hot or warm start-up and the released heat, the grid connection time is significantly shortened and flexible and rapid peak shaving is achieved; after the thermal power unit 200 completes the start-up, controls the thermal storage unit 400 to continuously release heat to the thermal power unit 200 to increase the total power generation.

[0032] refer to Figure 1 , Figure 2 as well as Figure 3 During off-peak electricity hours, when the grid load is low, the thermal-nuclear power coupling system 100A enters energy storage and insulation mode. At this time, the system extracts steam from the nuclear power unit 100 to reduce the amount of electricity fed into the grid. Specifically, the nuclear reactor 1 in the nuclear power unit 100 exchanges heat with the nuclear steam generator 2 to generate steam. A portion of the main steam extracted at the outlet of the nuclear steam generator 2 is divided into two parts. The first part, as the first extraction steam S10, is input into the thermal power unit 200, which is in a shutdown, no-heat-load state. The first extraction steam S10 flows sequentially through the thermal power boiler 6, the high-pressure cylinder 7 of the thermal power turbine, the thermal power reheater 8, the intermediate-pressure cylinder 9 of the thermal power turbine, and the low-pressure cylinder 10 of the thermal power turbine, deeply heating and insulating each flow path and heat exchange component of the thermal power unit, maintaining the entire unit at a warm or hot state. After releasing heat and maintaining its temperature, the steam is drawn from the exhaust side of the low-pressure cylinder 10 of the thermal power turbine or before the inlet of the thermal power condenser 11, forming thermal power return steam S11, which returns to the nuclear power unit 100 and enters the nuclear power turbine 3 to continue expanding and generating electricity. It then enters the nuclear power condenser 4 to be cooled and is sent back to the nuclear power steam generator 2 by the nuclear power circulating pump 5. Through this cross-unit steam insulation mechanism, since the thermal power boiler 6 is in a no-heat-load state, the heat source only needs to overcome the pipe flow resistance, resulting in small pressure and temperature drops, and can still return to the nuclear power unit 100 to generate electricity, thus maintaining the thermal power unit equipment at a hot state.

[0033] Simultaneously, the second portion of main steam extracted is input as the second extraction steam S20 into the first heat exchanger 13 of the heat pump unit 300, serving as the bottom-level low-temperature heat source of the heat pump system. The heat pump working fluid within the heat pump unit 300 absorbs heat from this low-temperature heat source in the first heat exchanger 13, and then enters the heat pump compressor 14. The heat pump compressor 14 consumes electricity to perform work, raising the temperature and pressure of the heat pump working fluid, transforming it from low-grade heat energy to high-grade heat energy. The heated heat pump working fluid then enters the second heat exchanger 15 to release heat, generating heat pump heating H1. This heat pump heating H1 heats the heat storage medium flowing from the low-temperature storage tank 17 in the heat storage unit 400, and stores the heat storage medium that has absorbed high-grade heat energy in the high-temperature storage tank 18, thereby achieving the conversion and efficient storage of low-grade heat energy into high-grade heat energy. The released nuclear power steam forms heat pump return steam S21 and returns to the nuclear power unit 100, while the released heat pump working fluid is depressurized by the heat pump depressurization device 16 and returns to the first heat exchanger 13 of the heat pump to complete the internal circulation.

[0034] During peak power periods, grid load demand increases, and the thermal power-nuclear power coupling system 100A receives a grid connection command and switches to energy release power generation mode. At this time, the thermal power unit 200 ignites and starts up. Because the thermal power unit 200 is always under the effect of cross-unit insulation during off-peak power periods, the core components maintain a good temperature. Therefore, the thermal power unit 200 can directly perform hot or warm start-up with the help of the insulation foundation, and its start-up ramp-up process is significantly shortened compared to the traditional cold start. At the same time, in order to make up for the power generation gap caused by the thermal power boiler 6 not being able to respond to the load in time during the initial stage of start-up ramp-up of the thermal power unit 200, the thermal energy storage unit 400 begins to release energy. Specifically, the high-temperature thermal energy storage medium in the high-temperature storage tank 18 is pumped out and sent to the thermal energy storage medium heat exchange device 19. The thermal power working fluid S30 from the thermal power unit 200, driven by the thermal power circulating pump 12, is introduced into the thermal energy storage medium heat exchange device 19 to absorb the high-grade heat of the high-temperature thermal energy storage medium, thereby generating additional steam S31 generated by the high-temperature thermal energy storage system. The additional steam S31 returns to the thermal power unit 200 and is directly integrated into the turbine unit for expansion and power generation. This perfectly compensates for the deficiency that the thermal power boiler cannot meet the power generation demand during the initial ramp-up startup phase. After the thermal power unit 200 completes startup and enters normal full-load operation, at the peak power generation time, the additional steam S31 continuously generated by the thermal storage unit 400 can continue to be added to the thermal power cycle, significantly increasing the total power generation capacity of the power plant.

[0035] This embodiment achieves deep coupling between the aforementioned units. On one hand, the first extraction steam S10 provides cross-unit insulation for the thermal power unit 200. Since the thermal power boiler 6 is in a no-heat-load state, the heat source only needs to overcome the flow resistance in the pipeline, resulting in small pressure and temperature drops, and can still return to the nuclear power unit 100 to generate electricity. This keeps the thermal power unit equipment at a hot state. On the other hand, the additional steam S31 generated by the thermal storage system is directly incorporated into the thermal power unit 200 to perform work, thereby compensating for the deficiency that the thermal power boiler 6 cannot meet the power generation demand during the initial startup and ramp-up phase.

[0036] The thermal power-nuclear power coupling system 100A provided in this embodiment, which improves the quality of thermal energy and enables flexible and rapid peak shaving, achieves the following: First, it enables rapid and flexible peak shaving for thermal power. By utilizing the nuclear power heat source to provide cross-unit insulation for the shut-down thermal power unit 200, it avoids equipment cooling and allows the thermal power unit to quickly perform hot start-up during peak power periods. Simultaneously, the high-temperature supplementary steam provided by the thermal storage unit 400 quickly compensates for the power shortage during the initial startup phase of the thermal power plant, significantly shortening the grid connection response time. When the thermal power unit 200 is operating normally, the continuously accumulated high-temperature supplementary steam can further increase the total power generation capacity of the power plant. Second, it improves the utilization quality of nuclear energy heat and achieves efficient energy storage. The heat pump unit 300 cleverly utilizes the redundant low-temperature heat source of nuclear power during off-peak periods, mechanically upgrading it into high-quality thermal energy for storage. This effectively improves the overall energy quality of the system and achieves efficient energy conversion. Third, it ensures the stable operation of the nuclear power unit. The thermal power-nuclear power coupling system 100A adapts to the peak and valley changes of the power grid by changing the steam extraction rate, avoiding frequent power regulation of the nuclear power reactor 1 and ensuring the safety and economy of the nuclear power unit 100.

[0037] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thermal nuclear power coupling system for improving the grade of thermal energy and achieving flexible and rapid peak regulation, characterized in that, include: Nuclear power units output heat sources that carry heat. A thermal power unit is connected to the pipeline of the nuclear power unit and receives at least a portion of the heat source output by the nuclear power unit for heat preservation. A heat pump unit is connected to the pipeline of the nuclear power unit, receives another part of the heat source output by the nuclear power unit, and improves the heat quality of the heat source; The thermal storage unit is connected to the heat pump unit for heat exchange, receives and stores heat from the heat pump unit; and the thermal storage unit is connected to the pipeline of the thermal power unit, releasing heat to the thermal power unit to generate electricity.

2. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 1, wherein, The nuclear power unit includes: Nuclear reactor; A nuclear power steam generator is connected to the nuclear power reactor for heat exchange to form the heat source; The heat source inlet of the nuclear power steam turbine is connected to the heat source outlet of the nuclear power steam generator. A nuclear power condenser, the heat source inlet of which is connected to the heat source outlet of the nuclear power turbine; and The nuclear power circulating pump has its heat source inlet connected to the heat source outlet of the nuclear power condenser, and its heat source outlet connected to the heat source inlet of the nuclear power steam generator.

3. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 2, wherein, The thermal power unit includes: Thermal power boilers; The high-pressure cylinder of the thermal power turbine has its heat source inlet connected to the heat source outlet of the thermal power boiler. The thermal power reheater has its heat source inlet connected to the heat source outlet of the high-pressure cylinder of the thermal power turbine. The heat source inlet of the intermediate-pressure cylinder of the thermal power turbine is connected to the heat source outlet of the thermal power reheater. The heat source inlet of the low-pressure cylinder of the thermal power turbine is connected to the heat source outlet of the intermediate-pressure cylinder of the thermal power turbine, and its heat source outlet is connected to the heat source inlet of the nuclear power unit.

4. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 3, wherein, The heat pump internally circulates a heat pump working fluid, and the heat pump unit includes: The heat pump first heat exchanger has its heat source inlet connected to the heat source outlet of the nuclear power steam generator, and its heat source outlet connected to the heat source inlet of the nuclear power steam generator. The heat source entering the heat pump first heat exchanger exchanges heat with the heat pump working fluid. A heat pump compressor, wherein the heat pump working fluid inlet is connected to the heat pump working fluid outlet of the first heat exchanger of the heat pump; The second heat exchanger of the heat pump has its heat pump working fluid inlet connected to the heat pump working fluid outlet of the heat pump compressor; and The heat pump pressure reduction device has its heat pump working fluid inlet connected to the heat pump working fluid outlet of the second heat exchanger of the heat pump.

5. The thermal power-nuclear power coupling system for improving thermal energy quality and achieving flexible and rapid peak shaving according to claim 4, characterized in that, The thermal storage unit circulates a thermal storage medium, and the thermal storage unit includes: A cryogenic storage tank, the outlet of which is connected to the inlet of the heat storage medium of the second heat exchanger of the heat pump; A high-temperature storage tank, the inlet of which is connected to the outlet of the heat storage medium of the second heat exchanger of the heat pump; and A heat exchange device for a heat storage medium, wherein the heat storage medium inlet is connected to the heat storage medium outlet of the high-temperature storage tank, and the heat storage medium outlet is connected to the heat storage medium inlet of the low-temperature storage tank.

6. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 5, wherein, The thermal power unit circulates a thermal power working fluid, and the thermal power unit also includes: A thermal power condenser, wherein the outlet of the thermal power working fluid is connected to the inlet of the thermal power working fluid of the heat storage medium heat exchange device, and the outlet of the thermal power working fluid of the heat storage medium heat exchange device is connected to the thermal power boiler and the inlet of the thermal power working fluid of the high-pressure cylinder of the thermal power turbine respectively, and the heat storage medium in the heat storage medium heat exchange device exchanges heat with the thermal power working fluid from the thermal power condenser. A thermal power circulating pump is connected to the pipeline between the thermal power condenser and the thermal power boiler, and between the thermal power condenser and the heat exchange equipment for the heat storage medium.

7. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 6, wherein, The thermal power unit also includes: The heat source inlet of the insulated inlet pipe is connected to the heat source outlet of the nuclear power steam generator, and the heat source outlet is connected to the heat source inlet of the thermal power boiler. The heat source inlet of the insulated return steam pipeline is connected to the pipe section between the heat source outlet of the low-pressure cylinder of the thermal power turbine and the heat source inlet of the thermal power condenser, and its heat source outlet is connected to the heat source inlet of the nuclear power turbine.

8. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 7, wherein, It also includes the adjustment and control unit; The regulating control unit is connected to the nuclear power unit, the thermal power unit, the heat pump unit, and the thermal storage unit respectively, and is configured to switch and adjust the valve opening on each pipeline according to the grid load status, so as to control the flow state of the heat source, the heat pump working fluid, the thermal storage medium, and the thermal power working fluid.

9. The thermal energy grade boosting and flexible and rapid peak load regulating system of coupling thermal power and nuclear power of claim 8, wherein, The system control logic configuration of the adjustment and control unit is as follows: Receive grid peak shaving commands and determine grid load status; When the grid load is determined to be during off-peak hours, the heat source output by the nuclear power unit is controlled to be extracted to reduce the amount of electricity fed into the grid; wherein, at least part of the heat source is connected to the thermal power unit which is in a shutdown state for heat preservation; another part of the heat source is input to the heat pump unit, the heat pump unit is controlled to improve the heat quality of the heat source, and the heat storage unit receives and stores the heat from the heat pump unit. When the grid load is determined to be during peak power, the thermal power unit is controlled to receive the grid connection command and start ignition; the thermal power unit is controlled to perform hot start or warm start by utilizing the insulation during off-peak power; and the thermal storage unit is controlled to release heat to the thermal power unit to generate electricity.

10. The thermal power-nuclear power coupling system for improving thermal energy quality and achieving flexible and rapid peak shaving according to claim 6, characterized in that, The nuclear power unit includes at least one of the following: pressurized water reactor, boiling water reactor, heavy water reactor, high-temperature gas-cooled reactor, sodium-cooled fast reactor, and molten salt reactor power generation or heating system; The energy conversion cycle of the thermal power unit includes at least one of the following: steam Rankine cycle, reheat Rankine cycle, gas-steam combined cycle, organic Rankine cycle, supercritical carbon dioxide cycle, cogeneration cycle, or combination of the above cycles. The heat pump working fluid circulating in the heat pump unit includes one or a combination of air, helium, argon or carbon dioxide. The heat storage medium flowing within the heat storage unit includes molten salt or inert particles.

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