Nuclear power peak shaving system coupled with heat pump energy storage

Abstract

The invention provides a nuclear power peak shaving system coupled with heat pump energy storage. The nuclear power peak shaving system comprises a nuclear power unit, a heat pump unit and an overheating Rankine cycle unit. Wherein the nuclear power unit is provided with a first steam circulation path and uses saturated steam in the first steam circulation path to generate power, and the superheated Rankine cycle unit is provided with a second steam circulation path and uses superheated steam in the second steam circulation path to generate power; the heat pump unit comprises a compression device and an expansion device, a passage between the input end of the compression device and the output end of the expansion device is used for absorbing heat from the first steam circulation passage in a peak shaving state, and a passage between the output end of the compression device and the input end of the expansion device is used for releasing heat to the second steam circulation passage in a peak state. According to the nuclear power peak regulation system coupled with heat pump energy storage disclosed by the invention, the power of a reactor does not need to be changed in the peak regulation process of the nuclear power unit, so that the nuclear power unit can safely and stably participate in peak regulation and peak regulation of a power grid.

Description

Technical Field

[0001] The present disclosure relates to the technical field of nuclear power peak regulation, and in particular to a nuclear power peak regulation system coupled with heat pump energy storage. Background Art

[0002] At present, nuclear power units participate in grid peak regulation mainly by shutting down or operating at reduced load (about 80%) according to grid dispatch requirements.

[0003] However, there are major problems in achieving peak load regulation by reducing the power of nuclear reactors. First, deep peak load regulation is difficult to achieve; second, changing the reactor power will seriously affect the safe and stable operation of the system and affect the core refueling cycle; third, implementing reactor power regulation is prone to thermal fatigue of pressure vessels and other structural materials, fuel burnup loss, wear of moving equipment parts, neutron flux oscillation in the reactor, uneven core temperature distribution and other safety issues. In addition, when nuclear power units track and adjust the grid frequency, power regulation will also have a certain impact on the life of control rod drive mechanisms, reactor pressure vessels, pressurizers, steam generators and other components.

[0004] In addition, there is still no better measure for nuclear power units to achieve power peak regulation by coupling new energy storage. First, the configuration of electrochemical energy storage has a high safety risk. Second, the nuclear power generation process is a medium-low temperature saturated steam Rankine cycle, and the temperature difference between the inlet and output ends of the steam generator is relatively low. The use of conventional heat storage technologies such as molten salt and thermal oil will cause a significant increase in the use of energy storage media, and the stored medium and low-grade thermal energy is difficult to use, resulting in low thermal efficiency for power generation. Summary of the invention

[0005] The present disclosure aims to solve one of the technical problems in the related art at least to some extent.

[0006] To this end, the purpose of the present disclosure is to provide a nuclear power peak-shaving system coupled with heat pump energy storage.

[0007] To achieve the above-mentioned purpose, the present disclosure provides a nuclear power peak-shaving system coupled with a heat pump energy storage, comprising: a nuclear power unit, a heat pump unit and a superheated Rankine cycle unit; wherein the nuclear power unit has a first steam circulation path and generates electricity using the saturated steam in the first steam circulation path, and the superheated Rankine cycle unit has a second steam circulation path and generates electricity using the superheated steam in the second steam circulation path; the heat pump unit comprises: a compression device and an expansion device, the path between the input end of the compression device and the output end of the expansion device is used to absorb heat from the first steam circulation path when in a peak-shaving state, and the path between the output end of the compression device and the input end of the expansion device is used to release heat to the second steam circulation path when in a peak state.

[0008] Optionally, the heat pump unit also includes: a heat absorber, a heat release channel of the heat absorber is connected in parallel to the first steam circulation passage, and the heat release channel of the heat absorber is connected in series between the input end of the compression device and the output end of the expansion device, the heat release channel input end of the heat absorber is connected to the output end of the expansion device, and the heat release channel output end of the heat absorber is connected to the input end of the compression device; a radiator, the heat release channel of the radiator is connected in series between the output end of the compression device and the input end of the expansion device, and the heat release channel input end of the radiator is connected to the output end of the compression device, the heat release channel output end of the radiator is connected to the input end of the expansion device, and the heat release channel of the radiator is connected in parallel to the second steam circulation passage.

[0009] Optionally, the heat pump unit also includes: a low-temperature tank, the output end of the low-temperature tank is connected to the input end of the heat absorption channel of the radiator; a high-temperature tank, the input end of the high-temperature tank is connected to the output end of the heat absorption channel of the radiator; a first steam generator, the heat release channel input end of the first steam generator is connected to the output end of the high-temperature tank, and the heat release channel output end of the first steam generator is connected to the input end of the low-temperature tank, and the heat absorption channel of the first steam generator is connected to the main steam heating channel in the second steam circulation path in parallel; a reheater, the heat release channel input end of the reheater is connected to the output end of the high-temperature tank, and the heat release channel output end of the reheater is connected to the input end of the low-temperature tank, and the heat absorption channel of the reheater is connected to the reheat steam heating channel in the second steam circulation path in parallel.

[0010] Optionally, the superheated Rankine cycle unit includes: a boiler, a first high-pressure cylinder, a first medium- and low-pressure cylinder, and a first generator; wherein the first high-pressure cylinder, the first medium- and low-pressure cylinder, and the first generator are sequentially connected in transmission; the input end of the first high-pressure cylinder is respectively connected to the output end of the main steam heating passage of the boiler and the output end of the heat absorption channel of the first steam generator, and the first output end of the first high-pressure cylinder is respectively connected to the input end of the reheat steam heating passage of the boiler and the input end of the heat absorption channel of the reheater; the input ends of the first medium- and low-pressure cylinders are respectively connected to the output end of the reheat steam heating passage of the boiler and the output end of the heat absorption channel of the reheater, and the first output ends of the first medium- and low-pressure cylinders are respectively connected to the input end of the main steam heating passage of the boiler and the input end of the heat absorption channel of the first steam generator.

[0011] Optionally, the superheated Rankine cycle unit also includes: a first condenser, a first low-pressure heater, a first deaerator and a first high-pressure heater; wherein, the input end of the first condenser is connected to the first output end of the first intermediate and low-pressure cylinder, and the output end of the first condenser is connected to the heat absorption channel input end of the first low-pressure heater, and the heat release channel input end of the first low-pressure heater is connected to the second output end of the first intermediate and low-pressure cylinder; the input end of the first deaerator is respectively connected to the heat absorption channel output end of the first low-pressure heater, the heat release channel output end of the first low-pressure heater and the third output end of the first intermediate and low-pressure cylinder, and the output end of the first deaerator is connected to the heat absorption channel input end of the first high-pressure heater; the heat release channel input end of the first high-pressure heater is connected to the second output end of the first high-pressure cylinder, and the heat release channel output end and the heat absorption channel output end of the first high-pressure heater are respectively connected to the main steam heating passage input end of the boiler and the heat absorption channel input end of the first steam generator.

[0012] Optionally, the first steam cycle path includes: a first loop and a second loop, the first loop is used to release heat to the second loop; wherein the path between the input end of the compression device and the output end of the expansion device is used to absorb heat from the first loop and / or the second loop when in a peak shaving state.

[0013] Optionally, the nuclear power unit includes: a reactor and a second steam generator; wherein the output end of the reactor is connected to the input end of the heat release channel of the second steam generator, and the input end of the reactor is connected to the output end of the heat release channel of the second steam generator, and the heat absorption channel of the second steam generator is connected in series in the second loop; the first loop is formed between the heat release channels of the reactor and the second steam generator, and the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the passage between the output end of the reactor and the input end of the reactor when in the peak shaving state.

[0014] Optionally, the nuclear power unit also includes: a second high-pressure cylinder, a second medium- and low-pressure cylinder, a heat exchanger and a second generator; wherein the second high-pressure cylinder, the second medium- and low-pressure cylinders and the second generator are sequentially connected in transmission; the input end of the second high-pressure cylinder and the input end of the heat release channel of the heat exchanger are respectively connected to the output end of the heat absorption channel of the second steam generator, and the first output end of the second high-pressure cylinder is connected to the input end of the heat absorption channel of the heat exchanger; the input end of the second medium- and low-pressure cylinder is connected to the output end of the heat absorption channel of the heat exchanger, and the first output end of the second medium- and low-pressure cylinder is connected to the input end of the heat absorption channel of the second steam generator; the second high-pressure cylinder, the second medium- and low-pressure cylinder and the heat exchanger form the second circuit, and the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the output end of the heat absorption channel of the second steam generator, the second output end of the second high-pressure cylinder and the second output end of the second medium- and low-pressure cylinders when in the peak shaving state.

[0015] Optionally, the nuclear power unit also includes: an ejector and a temperature reduction and pressure reduction device, the first input end of the ejector is connected to the output end of the heat absorption channel of the second steam generator, and the second input end of the ejector is connected to the second output end of the second high-pressure cylinder, the third input end of the ejector is connected to the second output end of the second medium and low-pressure cylinders, the output end of the ejector is connected to the input end of the temperature reduction and pressure reduction device, and the output end of the temperature reduction and pressure reduction device is connected to the input end of the heat absorption channel of the second steam generator; wherein the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the passage between the output end of the ejector and the input end of the temperature reduction and pressure reduction device when in the peak shaving state.

[0016] Optionally, the nuclear power unit also includes: a second condenser, a second low-pressure heater, a second deaerator and a second high-pressure heater; wherein the input end of the second condenser is connected to the first output end of the second medium and low-pressure cylinders, and the output end of the second condenser is connected to the heat absorption channel input end of the second low-pressure heater, and the heat release channel input end of the second low-pressure heater is connected to the third output end of the second medium and low-pressure cylinders; the input end of the second deaerator is respectively connected to the heat absorption channel output end of the second low-pressure heater, the heat release channel output end of the second low-pressure heater, the first output end of the second high-pressure cylinder and the output end of the temperature reduction and pressure reduction device, and the output end of the second deaerator is connected to the heat absorption channel input end of the second high-pressure heater; the heat release channel input end of the second high-pressure heater is respectively connected to the third output end of the second high-pressure cylinder and the heat release channel output end of the heat exchanger, and the heat release channel output end and the heat absorption channel output end of the second high-pressure heater are respectively connected to the heat absorption channel input end of the second steam generator.

[0017] The technical solution provided by the present disclosure may have the following beneficial effects:

[0018] By establishing a heat pump unit between a nuclear power unit that generates electricity using low-temperature saturated steam and a superheated Rankine cycle unit that generates electricity using high-temperature superheated steam, and utilizing the heat pump cycle of the heat pump unit to "transfer" the thermal energy of the peak-shaving steam in the nuclear power unit to the superheated Rankine cycle unit, the heat pump cycle can provide the superheated Rankine cycle unit with thermal energy that is several times the power consumption, ultimately achieving the purpose of improving the thermal efficiency of the system's power generation. At the same time, by coupling the heat pump unit and the superheated Rankine cycle unit in the nuclear power unit, the peak-shaving process of the nuclear power unit does not require changing the reactor power, thereby enabling the nuclear power unit to safely and stably participate in the peak-shaving and peaking of the power grid.

[0019] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present disclosure will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 It is a structural schematic diagram of a nuclear power peak-shaving system coupled with a heat pump energy storage proposed in an embodiment of the present disclosure;

[0022] Figure 2 It is a structural schematic diagram of a nuclear power peak-shaving system coupled with a heat pump energy storage proposed in an embodiment of the present disclosure (first embodiment);

[0023] Figure 3 It is a structural schematic diagram of a nuclear power peak-shaving system coupled with a heat pump energy storage proposed in one embodiment of the present disclosure (second embodiment);

[0024] As shown in the figure: 1. Nuclear power unit, 11. Reactor, 12. Second steam generator, 13. Second high-pressure cylinder, 14. Second medium- and low-pressure cylinder, 15. Heat exchanger, 16. Second generator, 17. Ejector, 18. Second condenser, 19. Second low-pressure heater, 110. Second deaerator, 111. Second high-pressure heater, 112. Temperature and pressure reduction device;

[0025] 2. heat pump unit, 21. compression device, 22. expansion device, 23. heat absorber, 24. heat emitter, 25. low temperature tank, 26. high temperature tank, 27. first steam generator, 28. reheater;

[0026] 3. Superheated Rankine cycle unit, 31. Boiler, 32. First high-pressure cylinder, 33. First medium- and low-pressure cylinders, 34. First generator, 35. First condenser, 36. First low-pressure heater, 37. First deaerator, 38. First high-pressure heater. DETAILED DESCRIPTION

[0027] Embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present disclosure, and are not to be construed as limitations of the present disclosure. On the contrary, the embodiments of the present disclosure include all changes, modifications, and equivalents that fall within the spirit and connotation of the appended claims.

[0028] like Figure 1 As shown, the embodiment of the present disclosure proposes a nuclear power peak-shaving system coupled with heat pump energy storage, comprising: a nuclear power unit 1, a heat pump unit 2 and a superheated Rankine cycle unit 3. The nuclear power unit 1 has a first steam cycle passage and generates electricity using saturated steam in the first steam cycle passage, and the superheated Rankine cycle unit 3 has a second steam cycle passage and generates electricity using superheated steam in the second steam cycle passage; the heat pump unit 2 comprises: a compression device 21 and an expansion device 22, the passage between the input end of the compression device 21 and the output end of the expansion device 22 is used to absorb heat from the first steam cycle passage when in the peak-shaving state, and the passage between the output end of the compression device 21 and the input end of the expansion device 22 is used to release heat to the second steam cycle passage when in the peak state.

[0029] It can be understood that the nuclear power unit 1 uses the saturated steam in the first steam circulation path to generate electricity, and the superheated Rankine cycle unit 3 uses the superheated steam in the second steam circulation path to generate electricity, thereby meeting the electricity demand of the power grid, and the path between the input end of the compression device 21 and the output end of the expansion device 22 absorbs heat from the first steam circulation path, thereby adjusting the load of the nuclear power unit 1 according to the heat absorption, and then adapting to the peak demand of the power grid. At the same time, the path between the output end of the compression device 21 and the input end of the expansion device 22 releases heat to the second steam circulation path, thereby increasing the heat of the superheated Rankine cycle unit 3 according to the heat release, thereby adapting to the peak demand of the power grid.

[0030] Among them, by establishing a heat pump unit 2 between a nuclear power unit 1 that generates electricity using low-temperature saturated steam and a superheated Rankine cycle unit 3 that generates electricity using high-temperature superheated steam, the heat pump cycle of the heat pump unit 2 is used to "transfer" the thermal energy of the peak-shaving steam in the nuclear power unit 1 to the superheated Rankine cycle unit 3. The heat pump cycle can provide the superheated Rankine cycle unit 3 with thermal energy that is several times the power consumption, ultimately achieving the purpose of improving the thermal efficiency of the system's power generation. At the same time, by coupling the heat pump unit 2 and the superheated Rankine cycle unit 3 in the nuclear power unit 1, the peak-shaving process of the nuclear power unit 1 does not require changing the power of the reactor 11, thereby enabling the nuclear power unit 1 to safely and stably participate in the peak-shaving and peaking of the power grid.

[0031] It should be noted that, based on the coupling of the heat pump unit 2 between the nuclear power unit 1 and the superheated Rankine cycle unit 3, the nuclear power unit 1 does not need to be shut down or run at reduced load when participating in the peak load regulation of the power grid, thereby avoiding the problems caused by reducing power. Specifically, firstly, without reducing power, it is easy to achieve deep peak load regulation by using the heat absorption and transfer control of the heat pump unit 2; secondly, the constant power enables the nuclear power unit 1 to operate safely and stably, and does not affect the core refueling cycle; finally, the constant power is not prone to thermal fatigue of pressure vessels and other structural materials, fuel burnup loss, wear of moving equipment parts, neutron flux oscillation in the reactor, uneven core temperature distribution and other safety problems. At the same time, without changing the power, it also avoids affecting the life of the control rod drive mechanism, the reactor 11 pressure vessel, the pressurizer, the steam generator and other components.

[0032] In addition, compared with other coupling peak-shaving methods in the relevant embodiments, the coupling method of the heat pump unit 2 and the superheated Rankine cycle unit 3 in the nuclear power unit 1 in this embodiment does not involve electrochemical reactions, has a higher safety factor, and uses the reverse Brayton cycle to achieve thermal energy quality improvement and value-added. Specifically, the steam heat of the nuclear power unit 1 is used as the low-temperature heat source of the heat pump unit 2, and the advantages of the heat pump unit 2 itself (COP>1) are used to "transfer" the steam heat to the superheated Rankine cycle unit 3, and the heat is increased in value. During peak power consumption, the nuclear power unit 1 can generate electricity in a conventional manner, and the heat transferred by the heat pump unit 2 can be coupled with the superheated Rankine cycle unit 3 to jointly generate electricity and improve the power generation capacity of the coupling system.

[0033] In summary, the nuclear power peak load regulation system of this embodiment can realize the safe and stable participation of the nuclear power unit 1 in the power peak load regulation, and at the same time improve the peak capacity of the unit, so that the unit has a higher operating flexibility. Among them, by coupling the heat pump unit 2 and the superheated Rankine cycle unit 3 in the nuclear power unit 1, it is ensured that the nuclear power unit 1 can operate at full power during peak load regulation, without affecting the core refueling cycle and maintenance, and improving the peak load regulation and top load capacity of the traditional nuclear power unit 1 in a safe, efficient and low-cost manner, providing better regulation capabilities for new energy power generation, ensuring the safety and stability of the new power system, and achieving positive social benefits while also bringing corresponding economic benefits to the nuclear power plant.

[0034] The nuclear power unit 1 is used to use nuclear energy to form saturated steam in the first steam circulation path therein, and use the saturated steam to generate electricity to meet electricity demand. The specific type of the nuclear power unit 1 can be set according to actual needs and is not limited to this.

[0035] The heat pump unit 2 is used to use the steam heat of the nuclear power unit 1 as a low-temperature heat source. At the same time, the compression device 21 is used to increase the pressure and temperature, and after releasing the heat, it is converted into mechanical work through the expansion device 22. The specific type of the heat pump unit 2 can be set according to actual needs and there is no restriction on this.

[0036] The compression device 21 and the expansion device 22 use a circulating working fluid to transfer energy. The circulating working fluid may be air, argon, nitrogen, helium, carbon dioxide, hydrogen, oxygen or a combination thereof, without limitation.

[0037] The specific types of the compression device 21 and the expansion device 22 can be set according to actual needs, and there is no limitation on this. For example, the compression device 21 can be a compressor, and the expansion device 22 can be an expander. The working fluid circulates between the compressor and the expander, and the compressor and the expander are connected by transmission. Specifically, the compressor can convert the low-pressure working fluid into a high-pressure state, and at the same time, increase the temperature of the working fluid by increasing the pressure; the expander can make the working fluid expand adiabatically inside, consume the internal energy of the working fluid itself, thereby greatly reducing the pressure and temperature of the working fluid, achieving the purpose of refrigeration and cooling. At the same time, the expander can output mechanical work to the outside during the expansion of the working fluid, which can convert the internal energy of the working fluid into mechanical energy.

[0038] The heat pump unit 2 can connect multiple systems in parallel according to the peak-shaving needs of the nuclear power unit 1. The system can receive electricity from the nuclear power unit 1, the superheated Rankine cycle unit 3 or an external power source (for example, a thermal power generation system, a wind power generation system, a solar photovoltaic power generation system, a power grid, a solar thermal power generation system, a nuclear power generation system, etc.).

[0039] The superheated Rankine cycle unit 3 is used to form superheated steam in the second steam cycle path therein using fuels such as coal and the heat "transferred" by the heat pump unit 2 from the nuclear power unit 1, and to generate electricity using the superheated steam, thereby meeting the electricity demand. The specific type of the superheated Rankine cycle unit 3 can be set according to actual needs, and there is no restriction on this. For example, the superheated Rankine cycle unit 3 can be a thermal power unit, and based on the heat pump unit 2, the combined peak load of thermal power and nuclear power is realized. Among them, the power generation of the heat pump unit 2 adopts the superheated steam Rankine cycle mode. Considering the problem of short peak load times of nuclear power, a coal-fired or gas-fired boiler 31 can be configured to realize independent power generation of the superheated steam Rankine cycle.

[0040] like Figure 1 , Figure 2 and Figure 3As shown, in some embodiments, the heat pump unit 2 also includes: a heat absorber 23 and a heat radiator 24, the heat release channel of the heat absorber 23 is connected in parallel to the first steam circulation path, and the heat release channel of the heat absorber 23 is connected in series between the input end of the compression device 21 and the output end of the expansion device 22, the heat release channel input end of the heat absorber 23 is connected to the output end of the expansion device 22, the heat release channel output end of the heat absorber 23 is connected to the input end of the compression device 21, the heat release channel of the heat radiator 24 is connected in series between the output end of the compression device 21 and the input end of the expansion device 22, and the heat release channel input end of the heat radiator 24 is connected to the output end of the compression device 21, the heat release channel output end of the heat radiator 24 is connected to the input end of the expansion device 22, and the heat release channel of the heat radiator 24 is connected in parallel to the second steam circulation path.

[0041] It can be understood that since the heat release channel of the heat absorber 23 is connected in parallel to the first steam circulation path, and the heat absorption channel of the heat absorber 23 is connected in series between the input end of the compression device 21 and the output end of the expansion device 22, when the circulating working fluid is transported from the output end of the expansion device 22 to the input end of the compression device 21, the heat exchange between the heat release channel and the heat absorption channel in the heat absorber 23 can be used to realize the transfer of steam heat in the first steam circulation path to the circulating working fluid.

[0042] Since the heat release channel of the heat release device 24 is connected in series between the output end of the compression device 21 and the input end of the expansion device 22, and the heat absorption channel of the heat release device 24 is connected in parallel to the second steam circulation path, when the circulating working fluid is transported from the output end of the compression device 21 to the input end of the expansion device 22, the heat in the circulating working fluid can be transferred to the first steam circulation path by utilizing the heat exchange between the heat release channel and the heat absorption channel in the heat release device 24.

[0043] Therefore, through the compression and temperature increase and pressure increase of the compression device 21 and the expansion and temperature decrease and pressure reduction of the expansion device 22, as well as the heat exchange between the absorber 23 and the emitter 24, the steam heat in the first steam circulation path can be used as a low-temperature heat source for the heat pump unit 2 based on the reverse Brayton cycle, and the advantage of COP>1 can be used to obtain heat value-added, thereby achieving quality improvement and value-added of nuclear energy during peak regulation, and then coupling the superheated Rankine cycle unit 3 to achieve peak high-efficiency power generation.

[0044] It should be noted that the heat absorber 23 and the heat radiator 24 are both used for heat exchange. From the perspective of the heat pump unit 2, the heat absorber 23 is used to absorb heat from the steam in the first steam circulation path, and the heat radiator 24 is used to release heat into the steam in the second steam circulation path. The heat absorber 23 and the heat radiator 24 both have heat absorption channels and heat exchange channels for direct or indirect heat exchange. The specific types of the heat absorber 23 and the heat radiator 24 can be set according to actual needs and are not limited to this.

[0045] like Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, the heat pump unit 2 also includes: a low-temperature tank 25, a high-temperature tank 26, a first steam generator 27 and a reheater 28, the output end of the low-temperature tank 25 is connected to the input end of the heat absorption channel of the radiator 24, the input end of the high-temperature tank 26 is connected to the output end of the heat absorption channel of the radiator 24, the input end of the heat release channel of the first steam generator 27 is connected to the output end of the high-temperature tank 26, and the output end of the heat release channel of the first steam generator 27 is connected to the input end of the low-temperature tank 25, the heat absorption channel of the first steam generator 27 is connected in parallel with the main steam heating channel in the second steam circulation channel, the heat release channel input end of the reheater 28 is connected to the output end of the high-temperature tank 26, and the heat release channel output end of the reheater 28 is connected to the input end of the low-temperature tank 25, and the heat absorption channel of the reheater 28 is connected in parallel with the reheat steam heating channel in the second steam circulation channel.

[0046] It can be understood that since the output end of the low-temperature tank 25 is connected to the input end of the heat absorption channel of the radiator 24, and the input end of the high-temperature tank 26 is connected to the output end of the heat absorption channel of the radiator 24, the energy storage medium in the low-temperature tank 25 can enter the high-temperature tank 26 through the heat absorption channel of the radiator 24, and when passing through the heat absorption channel of the radiator 24, the working fluid in the heat release channel of the radiator 24 can heat the energy storage medium in the heat absorption channel, thereby realizing the storage of heat in the energy storage medium.

[0047] Since the input end of the heat release channel of the first steam generator 27 is connected to the output end of the high-temperature tank 26, and the output end of the heat release channel of the first steam generator 27 is connected to the input end of the low-temperature tank 25, the heat absorption channel of the first steam generator 27 and the main steam heating channel in the second steam circulation channel are connected in parallel, so that the energy storage medium in the high-temperature tank 26 can enter the low-temperature tank 25 through the heat release channel of the first steam generator 27, and when passing through the heat release channel of the first steam generator 27, the energy storage medium can heat the water vapor in the heat absorption channel, thereby converting the water vapor into the main steam for power generation of the superheated Rankine cycle unit 3, thereby improving the power generation capacity of the system.

[0048] Since the input end of the heat release channel of the reheater 28 is connected to the output end of the high-temperature tank 26, and the output end of the heat release channel of the reheater 28 is connected to the input end of the low-temperature tank 25, the heat absorption channel of the reheater 28 and the reheat steam heating channel in the second steam circulation path are connected in parallel, so that the energy storage medium in the high-temperature tank 26 can enter the low-temperature tank 25 through the heat release channel of the reheater 28, and when passing through the heat release channel of the reheater 28, the energy storage medium can heat the water vapor in the heat absorption channel, thereby converting the water vapor into reheat steam for power generation by the superheated Rankine cycle unit 3, thereby improving the power generation capacity of the system.

[0049] Among them, in the peak-shaving state, the steam heat in the first steam circulation path is upgraded and increased in quality through compression and temperature and pressure increase by the compression device 21 and expansion and temperature and pressure reduction by the expansion device 22, as well as the heat exchange between the absorber 23 and the radiator 24, and then stored in the energy storage medium in the high-temperature tank 26; in the peak state, the nuclear power unit 1 uses the saturated steam in the first steam circulation path to generate electricity, and the superheated Rankine cycle unit 3 uses the superheated steam in the second steam circulation path to generate electricity. At the same time, the energy storage medium in the high-temperature tank 26 uses the heat exchange between the first steam generator 27 and the reheater 28 to release heat to the second steam circulation path, thereby improving the peak capacity of the system.

[0050] It should be noted that the low-temperature tank 25 is used to store low-temperature energy storage media, and the high-temperature tank 26 is used to store high-temperature energy storage media. The specific types of the low-temperature tank 25 and the high-temperature tank 26 can be set according to actual needs and are not limited to this.

[0051] The energy storage medium may be potassium nitrate, calcium nitrate, sodium nitrate, sodium nitrite, lithium nitrate, mineral oil or a mixture thereof, without limitation. In this embodiment, the energy storage medium is preferably solar salt to achieve solar salt molten salt heat storage.

[0052] In order to ensure the stable circulation of the energy storage medium, working fluid pumps may be provided at the output end of the low temperature tank 25 and the output end of the high temperature tank 26 respectively.

[0053] The first steam generator 27 and the reheater 28 are both used for heat exchange. The first steam generator 27 is used to heat the water vapor in the second steam circulation path into main steam using the heat in the energy storage medium. The reheater 28 is used to heat the water vapor in the second steam circulation path into reheated steam using the heat in the energy storage medium. The specific types of the first steam generator 27 and the reheater 28 can be set according to actual needs and are not limited to this.

[0054] As for the operating principle of the heat pump unit 2, for example, the external input electricity generates mechanical energy in the motor, drives the compression device 21 to work, compresses the low-temperature and low-pressure circulating working fluid at the input end of the compression device 21 into a high-temperature and high-pressure state, and then the circulating working fluid in the high-temperature and high-pressure state enters the heat release device 24, exchanges heat with the low-temperature energy storage medium coming in the opposite direction, and the heated low-temperature energy storage medium enters the high-temperature tank 26 to store the heat of the high-temperature and high-pressure circulating working fluid; the circulating working fluid after cooling enters the expansion device 22 to expand and do work, and the low-temperature and low-pressure circulating working fluid enters the heat absorber 23 from the output end of the expansion device 22, exchanges heat with the high-temperature steam coming in the opposite direction, and changes to a medium-temperature and low-pressure state to enter the input end of the compression device 21. This cycle "transfers" the heat of the high-temperature steam in the heat absorber 23 to the high-temperature heat medium through the heat pump cycle and stores it, and obtains the added value of heat through the heat pump's own advantage of COP>1.

[0055] The heat pump unit 2 can use one or more compression devices 21, one or more expansion devices 22, one or more heat absorbers 23, one or more heat emitters 24, one or more low-temperature heat sources (nuclear power units 1), and one or more radiators (superheated Rankine cycle units 3).

[0056] like Figure 2 and Figure 3 As shown, in some embodiments, the superheated Rankine cycle unit 3 includes: a boiler 31, a first high-pressure cylinder 32, a first medium-low pressure cylinder 33 and a first generator 34. The first high-pressure cylinder 32, the first medium-low pressure cylinder 33 and the first generator 34 are sequentially connected in transmission, the input end of the first high-pressure cylinder 32 is respectively connected to the output end of the main steam heating passage of the boiler 31 and the output end of the heat absorption passage of the first steam generator 27, and the first output end of the first high-pressure cylinder 32 is respectively connected to the input end of the reheat steam heating passage of the boiler 31 and the input end of the heat absorption passage of the reheater 28, the input end of the first medium-low pressure cylinder 33 is respectively connected to the output end of the reheat steam heating passage of the boiler 31 and the output end of the heat absorption passage of the reheater 28, and the first output end of the first medium-low pressure cylinder 33 is respectively connected to the input end of the main steam heating passage of the boiler 31 and the input end of the heat absorption passage of the first steam generator 27.

[0057] It can be understood that since the input end of the first high-pressure cylinder 32 is connected to the output end of the main steam heating passage of the boiler 31, and the first output end of the first high-pressure cylinder 32 is connected to the input end of the reheat steam heating passage of the boiler 31, the input end of the first intermediate and low-pressure cylinder 33 is connected to the output end of the reheat steam heating passage of the boiler 31, and the first output end of the first intermediate and low-pressure cylinder 33 is connected to the input end of the main steam heating passage of the boiler 31, the condensate output from the first output end of the first intermediate and low-pressure cylinder 33 can be converted into main steam when passing through the main steam heating passage of the boiler 31, and the main steam passes through the reheat steam heating passage of the boiler 31 and is converted into reheat steam after doing work in the first high-pressure cylinder 32, and the reheated steam is converted into condensate again after doing work in the first intermediate and low-pressure cylinder 33. Therefore, the heating of the boiler 31 and the circulation of condensate can be used to achieve efficient power generation of the first generator 34.

[0058] Furthermore, since the input end of the first high-pressure cylinder 32 is connected to the output end of the heat absorption channel of the first steam generator 27, and the first output end of the first high-pressure cylinder 32 is connected to the input end of the heat absorption channel of the reheater 28, the input end of the first intermediate and low-pressure cylinder 33 is connected to the output end of the heat absorption channel of the reheater 28, and the first output end of the first intermediate and low-pressure cylinder 33 is connected to the input end of the heat absorption channel of the first steam generator 27, the condensate output from the first output end of the first intermediate and low-pressure cylinder 33 can be converted into main steam when passing through the heat absorption channel of the first steam generator 27, and the main steam passes through the heat absorption channel of the reheater 28 and is converted into reheated steam after doing work in the first high-pressure cylinder 32, and the reheated steam is converted into condensate again after doing work in the first intermediate and low-pressure cylinder 33. Therefore, the power generation capacity of the first generator 34 can be effectively improved by utilizing the heating of the first steam generator 27 and the reheater 28 and the circulation of condensate.

[0059] It should be noted that the boiler 31 is used to heat water vapor using fuel such as coal to generate main steam for the first high-pressure cylinder 32 and reheated steam for the first medium- and low-pressure cylinders 33. The specific type of the boiler 31 can be set according to actual needs and is not limited to this.

[0060] The first high-pressure cylinder 32 is used to utilize the work of main steam to drive the first generator 34 to operate and generate electricity, and the first medium- and low-pressure cylinder 33 is used to utilize the work of reheated steam to drive the first generator 34 to operate and generate electricity. The specific types of the first high-pressure cylinder 32 and the first medium- and low-pressure cylinder 33 can be set according to actual needs and are not limited to this.

[0061] The first generator 34 is used to convert mechanical energy into electrical energy under the drive of the first high-pressure cylinder 32 and the first medium-low pressure cylinder 33. The specific type of the first generator 34 can be set according to actual needs and is not limited to this.

[0062] like Figure 2 and Figure 3As shown, in some embodiments, the superheated Rankine cycle unit 3 further includes: a first condenser 35 , a first low-pressure heater 36 , a first deaerator 37 and a first high-pressure heater 38 . Among them, the input end of the first condenser 35 is connected to the first output end of the first intermediate and low pressure cylinder 33, and the output end of the first condenser 35 is connected to the input end of the heat absorption channel of the first low pressure heater 36, the heat release channel input end of the first low pressure heater 36 is connected to the second output end of the first intermediate and low pressure cylinder 33, the input end of the first deaerator 37 is respectively connected to the heat absorption channel output end of the first low pressure heater 36, the heat release channel output end of the first low pressure heater 36 and the third output end of the first intermediate and low pressure cylinder 33, and the output end of the first deaerator 37 is connected to the heat absorption channel input end of the first high pressure heater 38, the heat release channel input end of the first high pressure heater 38 is connected to the second output end of the first high pressure cylinder 32, and the heat release channel output end and the heat absorption channel output end of the first high pressure heater 38 are respectively connected to the main steam heating passage input end of the boiler 31 and the heat absorption channel input end of the first steam generator 27.

[0063] It can be understood that, since the input end of the first condenser 35 is connected to the first output end of the first intermediate and low pressure cylinder 33, and the output end of the first condenser 35 is connected to the input end of the heat absorption channel of the first low pressure heater 36, the steam after the work of the first intermediate and low pressure cylinder 33 can be converted into condensed water by the first condenser 35 and transported to the heat absorption channel of the first low pressure heater 36; since the input end of the heat release channel of the first low pressure heater 36 is connected to the second output end of the first intermediate and low pressure cylinder 33, and the input end of the first deaerator 37 is respectively connected to the output end of the heat absorption channel of the first low pressure heater 36, the output end of the heat release channel of the first low pressure heater 36 and the third output end of the first intermediate and low pressure cylinder 33, the condensed water can be converted into condensed water by the first condenser 35 and transported to the heat absorption channel of the first low pressure heater 36. The steam is preheated, and the preheated condensed water and the water vapor after releasing heat enter the first deaerator 37 for deoxygenation; since the heat release channel input end of the first high-pressure heater 38 is connected to the second output end of the first high-pressure cylinder 32, and the heat release channel output end and the heat absorption channel output end of the first high-pressure heater 38 are respectively connected to the main steam heating passage input end of the boiler 31 and the heat absorption passage input end of the first steam generator 27, the deoxygenated water after deoxygenation can be further preheated by the steam of the first high-pressure cylinder 32, and the preheated deoxygenated water and the water vapor after releasing heat enter the main steam heating passage of the boiler 31 and the heat absorption passage of the first steam generator 27 and are converted into main steam, thereby realizing the steam circulation in the second steam circulation passage.

[0064] It should be noted that the first condenser 35 is used to utilize the heat exchange of cooling water to realize the condensation of steam, so that the steam after work in the first intermediate and low pressure cylinders 33 is converted into condensed water. The specific type of the first condenser 35 can be set according to actual needs and is not limited to this.

[0065] The first low-pressure heater 36 and the first high-pressure heater 38 are both used for preheating condensate. The first low-pressure heater 36 is used to preheat condensate using the steam in the first medium-low pressure cylinder 33, and the first high-pressure heater 38 is used to preheat deoxygenated water using the steam in the first high-pressure cylinder 32. The specific types of the first low-pressure heater 36 and the first high-pressure heater 38 can be set according to actual needs and are not limited to this.

[0066] The first deaerator 37 is used to remove oxygen from the condensate to reduce corrosion to the system. The specific type of the first deaerator 37 can be set according to actual needs and is not limited to this.

[0067] In order to ensure the stable circulation of water vapor, working medium pumps may be respectively provided at the output end of the first condenser 35 and the output end of the first deaerator 37 .

[0068] As for the operating principle of the superheated Rankine cycle unit 3, for example, the high-pressure and low-temperature feed water at the output end of the first high-pressure heater 38 enters the first steam generator 27 and the boiler 31 respectively, and becomes high-temperature and high-pressure main steam, and then enters the first high-pressure cylinder 32 and the first medium and low-pressure cylinders 33 in turn for expansion and power generation, and then enters the first condenser 35 to condense into a liquid state, and then passes through the first low-pressure heater 36, the first deaerator 37 and the first high-pressure heater 38 in turn to be heated into a low-temperature and high-pressure state and enters the first steam generator 27 and the boiler 31, thereby completing the heat absorption-discharge cycle.

[0069] In some embodiments, the first steam cycle path includes: a primary circuit and a secondary circuit, wherein the primary circuit is used to release heat to the secondary circuit. The path between the input end of the compression device 21 and the output end of the expansion device 22 is used to absorb heat from the primary circuit and / or the secondary circuit when in peak load state.

[0070] It can be understood that by using the steam heat of the primary and / or secondary circuits in the nuclear power unit 1 as the low-temperature heat source of the heat pump unit 2 based on the reverse Brayton cycle, and by establishing a heat pump cycle between the nuclear power unit 1 and the superheated Rankine cycle unit 3, the quality and value of nuclear energy can be improved during the peak regulation period of the unit, so as to achieve peak efficient power generation.

[0071] It should be noted that the first circuit is used to generate heat using nuclear energy reactions, and the second circuit is used to generate electricity based on the heat generated by the first circuit. The specific types of the first circuit and the second circuit can be set according to actual needs and there is no restriction on this.

[0072] like Figure 3As shown, in some embodiments, the nuclear power unit 1 includes: a reactor 11 and a second steam generator 12. The output end of the reactor 11 is connected to the input end of the heat release channel of the second steam generator 12, and the input end of the reactor 11 is connected to the output end of the heat release channel of the second steam generator 12, the heat absorption channel of the second steam generator 12 is connected in series in the secondary loop, a loop is formed between the heat release channels of the reactor 11 and the second steam generator 12, and the passage between the input end of the compression device 21 and the output end of the expansion device 22 is used to absorb heat from the passage between the output end of the reactor 11 and the input end of the reactor 11 when in the peak load state.

[0073] It can be understood that, since the output end of the reactor 11 is connected to the input end of the heat release channel of the second steam generator 12, and the input end of the reactor 11 is connected to the output end of the heat release channel of the second steam generator 12, a loop with circulating steam is formed between the heat release channels of the reactor 11 and the second steam generator 12, and since the heat absorption channel of the second steam generator 12 is connected in series in the second loop, heat can be transferred between the first loop and the second loop by utilizing the heat exchange between the heat absorption channel and the heat release channel in the second steam generator 12, thereby utilizing the transferred heat to realize power generation of the nuclear power unit 1.

[0074] In addition, the passage between the input end of the compression device 21 and the output end of the expansion device 22 absorbs heat from the passage between the output end of the reactor 11 and the input end of the reactor 11, thereby adjusting the load of the nuclear power unit 1 according to the heat absorption, and then adapting to the peak regulation demand of the power grid.

[0075] It should be noted that the reactor 11 is used to utilize the nuclear energy generated by nuclear fission or nuclear fusion, convert it into heat energy, and then convert it into electrical energy through the cooperation of the primary circuit and the secondary circuit. The specific type of the reactor 11 can be set according to actual needs and is not limited to this. Among them, the output end of the reactor 11 is connected to the input end of the heat release channel of the heat absorber 23, and the input end of the reactor 11 is connected to the output end of the heat release channel of the heat absorber 23, thereby realizing the heat transfer of the primary circuit.

[0076] The second steam generator 12 is used to utilize the heat generated by the reactor 11 to heat the water vapor in the secondary circuit into saturated steam, so that the secondary circuit utilizes the saturated steam to generate electricity. The specific type of the second steam generator 12 can be set according to actual needs and is not limited to this.

[0077] In order to ensure the stable circulation of water vapor, a working fluid pump may be provided at the output end of the heat release channel of the second steam generator 12 .

[0078] like Figure 2As shown, in some embodiments, the nuclear power unit 1 further includes: a second high-pressure cylinder 13 , a second medium- and low-pressure cylinder 14 , a heat exchanger 15 and a second generator 16 . Among them, the second high-pressure cylinder 13, the second intermediate and low-pressure cylinder 14 and the second generator 16 are connected in sequence by transmission, the input end of the second high-pressure cylinder 13 and the input end of the heat release channel of the heat exchanger 15 are respectively connected to the output end of the heat absorption channel of the second steam generator 12, and the first output end of the second high-pressure cylinder 13 is connected to the input end of the heat absorption channel of the heat exchanger 15, the input end of the second intermediate and low-pressure cylinder 14 is connected to the output end of the heat absorption channel of the heat exchanger 15, and the first output end of the second intermediate and low-pressure cylinder 14 is connected to the input end of the heat absorption channel of the second steam generator 12, a second circuit is formed between the second high-pressure cylinder 13, the second intermediate and low-pressure cylinder 14 and the heat exchanger 15, and the passage between the input end of the compression device 21 and the output end of the expansion device 22 is used to absorb heat from the output end of the heat absorption channel of the second steam generator 12, the second output end of the second high-pressure cylinder 13 and the second output end of the second intermediate and low-pressure cylinder 14 when in the peak shaving state.

[0079] It can be understood that since the input end of the second high-pressure cylinder 13 and the input end of the heat release channel of the heat exchanger 15 are respectively connected to the output end of the heat absorption channel of the second steam generator 12, and the first output end of the second high-pressure cylinder 13 is connected to the input end of the heat absorption channel of the heat exchanger 15, the input end of the second intermediate and low-pressure cylinder 14 is connected to the output end of the heat absorption channel of the heat exchanger 15, and the first output end of the second intermediate and low-pressure cylinder 14 is connected to the input end of the heat absorption channel of the second steam generator 12, the condensate output from the first output end of the second intermediate and low-pressure cylinder 14 can be converted into main steam when passing through the heat absorption channel of the second steam generator 12, and the main steam passes through the heat absorption channel of the heat exchanger 15 and is converted into reheated steam after doing work in the second high-pressure cylinder 13, and the reheated steam is converted into condensate again after doing work in the second intermediate and low-pressure cylinder 14, thereby, the heating of the second steam generator 12, the heating of the heat exchanger 15 and the circulation of condensate can achieve efficient power generation of the second generator 16.

[0080] In addition, the passage between the input end of the compression device 21 and the output end of the expansion device 22 absorbs heat from the output end of the heat absorption channel of the second steam generator 12, the second output end of the second high-pressure cylinder 13 and the second output end of the second medium and low-pressure cylinder 14, thereby adjusting the load of the nuclear power unit 1 according to the heat absorption, and then adapting to the peak-shaving demand of the power grid.

[0081] It should be noted that the heat exchanger 15 is used to utilize the heat in the second steam generator 12 to heat the steam after the second high-pressure cylinder 13 has done work, so as to achieve reheated steam. The heat exchanger 15 has a heat absorption channel and a heat exchange channel for direct or indirect heat exchange. The specific type of the heat exchanger 15 can be set according to actual needs and is not limited to this.

[0082] The second high-pressure cylinder 13 is used to utilize the work of main steam to drive the second generator 16 to operate and generate electricity, and the second medium- and low-pressure cylinder 14 is used to utilize the work of reheated steam to drive the second generator 16 to operate and generate electricity. The specific types of the second high-pressure cylinder 13 and the second medium- and low-pressure cylinder 14 can be set according to actual needs and are not limited to this.

[0083] The second generator 16 is used to convert mechanical energy into electrical energy under the drive of the second high-pressure cylinder 13 and the second medium- and low-pressure cylinder 14. The specific type of the second generator 16 can be set according to actual needs and is not limited to this.

[0084] like Figure 2 As shown, in some embodiments, the nuclear power unit 1 further includes: an ejector 17 and a temperature reduction and pressure reduction device 112, the first input end of the ejector 17 is connected to the output end of the heat absorption channel of the second steam generator 12, and the second input end of the ejector 17 is connected to the second output end of the second high-pressure cylinder 13, the third input end of the ejector 17 is connected to the second output end of the second medium and low-pressure cylinder 14, the output end of the ejector 17 is connected to the input end of the temperature reduction and pressure reduction device 112, and the output end of the temperature reduction and pressure reduction device 112 is connected to the input end of the heat absorption channel of the second steam generator 12. Among them, the passage between the input end of the compression device 21 and the output end of the expansion device 22 is used to absorb heat from the passage between the output end of the ejector 17 and the input end of the temperature reduction and pressure reduction device 112 when in the peak load state.

[0085] It can be understood that since the first input end of the ejector 17 is connected to the output end of the heat absorption channel of the second steam generator 12, and the second input end of the ejector 17 is connected to the second output end of the second high-pressure cylinder 13, the third input end of the ejector 17 is connected to the second output end of the second medium and low-pressure cylinder 14, the output end of the ejector 17 is connected to the input end of the temperature reduction and pressure reduction device 112, and the output end of the temperature reduction and pressure reduction device 112 is connected to the input end of the heat absorption channel of the second steam generator 12, the passage between the input end of the compression device 21 and the output end of the expansion device 22 can utilize the ejection of the ejector 17 and the temperature reduction and pressure reduction of the temperature reduction and pressure reduction device 112 to absorb heat from the output end of the heat absorption channel of the second steam generator 12, the second output end of the second high-pressure cylinder 13 and the second output end of the second medium and low-pressure cylinder 14, thereby adjusting the load of the nuclear power unit 1 according to the heat absorption, and then adapting to the peak regulation demand of the power grid.

[0086] It should be noted that the ejector 17 is used to eject part of the steam at the output end of the heat absorption channel of the second steam generator 12, part of the steam at the second output end of the second high-pressure cylinder 13, and part of the steam at the second output end of the second medium and low-pressure cylinder 14 through the heat release channel of the heat absorber 23, so as to realize heat transfer. The specific type of the ejector 17 can be set according to actual needs and is not limited to this.

[0087] The temperature reduction and pressure reduction device 112 is used to reduce the temperature and pressure of the steam after heat release to protect the rear equipment, such as: deaerator, etc. The specific type of the temperature reduction and pressure reduction device 112 can be set according to actual needs and is not limited to this.

[0088] The secondary steam extraction of nuclear power unit 1 can use the main steam alone. Taking into account the axial thrust imbalance of the steam turbine, it can also use a variety of steam extraction methods such as "three extractions" (extraction of high, medium and low pressure cylinders), "four extractions" (extraction of main steam and high, medium and low pressure cylinders), connecting pipe extraction, cold and hot re-extraction, etc. In addition, the peak-shaving utilization of nuclear island cooling water is also considered.

[0089] like Figure 2 As shown, in some embodiments, the nuclear power unit 1 further includes: a second condenser 18 , a second low-pressure heater 19 , a second deaerator 110 and a second high-pressure heater 111 . Among them, the input end of the second condenser 18 is connected to the first output end of the second intermediate and low pressure cylinder 14, and the output end of the second condenser 18 is connected to the heat absorption channel input end of the second low pressure heater 19, the heat release channel input end of the second low pressure heater 19 is connected to the third output end of the second intermediate and low pressure cylinder 14, the input end of the second deaerator 110 is respectively connected to the heat absorption channel output end of the second low pressure heater 19, the heat release channel output end of the second low pressure heater 19, the first output end of the second high pressure cylinder 13 and the output end of the temperature reduction and pressure reduction device 112, and the output end of the second deaerator 110 is connected to the heat absorption channel input end of the second high pressure heater 111, the heat release channel input end of the second high pressure heater 111 is respectively connected to the third output end of the second high pressure cylinder 13 and the heat release channel output end of the heat exchanger 15, and the heat release channel output end and the heat absorption channel output end of the second high pressure heater 111 are respectively connected to the heat absorption channel input end of the second steam generator 12.

[0090] It can be understood that, since the input end of the second condenser 18 is connected to the first output end of the second intermediate and low pressure cylinder 14, and the output end of the second condenser 18 is connected to the input end of the heat absorption channel of the second low pressure heater 19, the steam after the second intermediate and low pressure cylinder 14 does work can be converted into condensed water by the second condenser 18 and transported to the heat absorption channel of the second low pressure heater 19; since the heat release channel input end of the second low pressure heater 19 is connected to the third output end of the second intermediate and low pressure cylinder 14, and the input end of the second deaerator 110 is respectively connected to the heat absorption channel output end of the second low pressure heater 19, the heat release channel output end of the second low pressure heater 19, the first output end of the second high pressure cylinder 13 and the output end of the temperature reduction and pressure reduction device 112, the condensed water can be converted into condensed water by the second condenser 18 and transported to the heat absorption channel of the second low pressure heater 19. The steam of the second medium and low pressure cylinders 14 is preheated, and the preheated condensed water and the water vapor after releasing heat enter the second deaerator 110 for deoxygenation; since the heat release channel input end of the second high pressure heater 111 is respectively connected to the third output end of the second high pressure cylinder 13 and the heat release channel output end of the heat exchanger 15, and the heat release channel output end and the heat absorption channel output end of the second high pressure heater 111 are respectively connected to the heat absorption channel input end of the second steam generator 12, the deoxygenated water after deoxygenation can be further preheated by the steam of the second high pressure cylinder 13 and the steam of the heat exchanger 15, and the preheated deoxygenated water and the water vapor after releasing heat enter the heat absorption channel of the second steam generator 12 and are converted into main steam, thereby realizing the steam circulation in the first steam circulation path.

[0091] It should be noted that the second condenser 18 is used to condense steam by utilizing heat exchange of cooling water, so that the steam after work in the second intermediate and low pressure cylinders 14 is converted into condensed water. The specific type of the second condenser 18 can be set according to actual needs and is not limited to this.

[0092] The second low-pressure heater 19 and the second high-pressure heater 111 are both used for preheating condensate. The second low-pressure heater 19 is used for preheating condensate using the steam in the second medium and low-pressure cylinder 14, and the second high-pressure heater 111 is used for preheating deoxygenated water using the steam in the second high-pressure cylinder 13. The specific types of the second low-pressure heater 19 and the second high-pressure heater 111 can be set according to actual needs and are not limited to this.

[0093] The second deaerator 110 is used to remove oxygen from the condensate to reduce corrosion of the system. The specific type of the second deaerator 110 can be set according to actual needs and is not limited to this.

[0094] In order to ensure the stable circulation of water vapor, working fluid pumps may be provided at the output end of the second condenser 18 and the output end of the second deaerator 110 , respectively.

[0095] Among them, the condensate temperature after the extraction steam passes through the heat absorber 23 is related to the extraction steam flow rate and the selection of the heat exchanger 15. In addition to the above-mentioned method of throttling and reducing the pressure of the condensate after the heat absorber 23 and then passing it into the second deaerator 110 of the secondary circuit of the nuclear power unit 1, it can also be considered to directly pump it into the heat absorption channel of the East 2 high-pressure heater, or pump it around the regenerators of various other secondary circuits.

[0096] As for the operating principle of the nuclear power unit 1, for example, the heat generated by nuclear fission of the nuclear fuel in the reactor 11 heats the primary high-pressure water, and transfers the heat to the secondary feed water through the second steam generator 12, heating the low-temperature high-pressure feed water at the output end of the second high-pressure heater 111 into high-temperature and high-pressure saturated steam, and then enters the second high-pressure cylinder 13 and the second medium and low-pressure cylinders 14 in sequence to generate electricity.

[0097] For the selection of multiple paths in the nuclear power peak-shaving system, automatic control can be achieved by using valve groups, which will not be described in detail here.

[0098] In the nuclear power peak-shaving system of this embodiment, a coupling structure of a nuclear power unit 1, a heat pump unit 2 and a superheated Rankine cycle unit 3 is provided, the steam heat of the nuclear power unit 1 is used as the low-temperature heat source of the heat pump unit 2, and the advantages of the heat pump unit 2 itself (COP>1) are used to "transfer" the steam heat to the high-temperature energy storage medium, and the heat is increased in value. During the peak period of electricity consumption, the nuclear power unit 1 can generate electricity in a conventional manner, and the heat stored in the heat pump unit 2 can be coupled with the boiler 31 in the superheated Rankine cycle unit 3 to jointly provide high-quality steam for the steam turbine, and generate electricity by work, thereby improving the power generation capacity of the coupling system.

[0099] like Figure 2 As shown, the first embodiment:

[0100] During the peak-shaving stage of the nuclear power unit 1, a portion of the saturated high-temperature steam at the output end of the second steam generator 12, a portion of the extraction steam from the second high-pressure cylinder 13, and a portion of the extraction steam from the second medium- and low-pressure cylinder 14 can be extracted through the ejector 17 and enter the heat absorber 23, and the heat is "transferred" to the high-temperature energy storage medium by the heat pump unit 2 and stored through the high-temperature tank 26, and the heat value is increased by the advantage of the heat pump system COP>1, and the extraction steam is cooled and decompressed (or only decompressed) and then re-enters the second deaerator 110 of the nuclear power unit 1. Among them, the power of the heat pump unit 2 can use renewable energy or use the power of the nuclear power unit 1 to further peak the unit.

[0101] During peak electricity consumption periods, the nuclear power unit 1 can generate electricity in a conventional operating mode. The high-temperature energy storage medium stored in the high-temperature tank 26 of the heat pump unit 2 is pumped out by a working fluid pump and divided into two parts, one part enters the first steam generator 27, and the other part enters the reheater 28.

[0102] The low-temperature and high-pressure feed water at the output end of the first high-pressure heater 38 is divided into two parts. One part enters the first steam generator 27, and is heated into high-temperature and high-pressure steam using the heat of the high-temperature medium stored in the high-temperature tank 26 of the heat pump unit 2 as a heat source; the other part enters the boiler 31, and is heated into high-temperature and high-pressure steam using the heat emitted by the combustion of fuels such as coal and natural gas as a heat source, and then merges with the steam at the output end of the first steam generator 27 and enters the first high-pressure cylinder 32 to expand and do work. Similarly, the exhaust steam of the first high-pressure cylinder 32 is also divided into two parts. One part enters the reheater 28, absorbs the heat of the energy storage medium of the heat pump unit 2 and becomes high-temperature and high-pressure reheat steam; the other part of the exhaust steam enters the boiler 31, and becomes high-temperature and high-pressure reheat steam after absorbing heat, and merges with the steam at the output end of the reheater 28 and enters the first medium and low pressure cylinder 33 to continue to expand and do work.

[0103] The exhaust steam from the first intermediate and low pressure cylinder 33 enters the condenser, is condensed into liquid by cooling water, and then enters the first low pressure heater 36, the first deaerator 37 and the first high pressure heater 38 in sequence, absorbs the heat of the extraction steam from the first intermediate and low pressure cylinder 33 and the first high pressure cylinder 32, and gradually heats up, and finally re-enters the boiler 31 and the first steam generator 27 to complete the power generation cycle.

[0104] Second embodiment:

[0105] like Figure 3 As shown, during the peak load period of nuclear power, a part of the high-temperature and high-pressure steam at the output end of the reactor 11 is extracted as the low-temperature heat source of the heat pump unit 2 and passed into the absorber 23. After the low-temperature and low-pressure working fluid at the output end of the expander absorbs the heat of the steam in the absorber 23, it enters the compression device 21, and after the temperature and pressure are increased, it enters the heat release device 24 to exchange heat with the low-temperature energy storage medium coming in the opposite direction. After the low-temperature energy storage medium absorbs the heat, it becomes a high-temperature energy storage medium and is stored in the high-temperature tank 26. The cooled circulating working fluid returns to the input end of the expansion device 22 to complete the heat storage cycle, and the cooled high-temperature and high-pressure steam in the absorber 23 returns to the nuclear power unit 1 to continue to absorb the heat of the reactor 11 to complete the cycle.

[0106] In the nuclear power peak-shaving system of this embodiment, the cooling water extracted from the primary circuit or the steam extracted from the secondary circuit of the nuclear power unit 1 is used as the low-temperature heat source of the heat pump unit 2 based on the reverse Brayton cycle, and the combined peak-shaving of the saturated steam Rankine cycle (such as the nuclear power unit 1) and the superheated steam Rankine cycle (such as the subcritical thermal power unit) is realized through the heat pump energy storage technology. At the same time, by establishing a heat pump cycle between the peak-shaving steam extraction of the nuclear power unit 1 and the high-temperature heat storage system, the quality and value of nuclear energy are improved during the peak-shaving period of the unit, so as to achieve peak efficient power generation. In addition, the heat pump energy storage power generation process of nuclear power peak-shaving can be coupled with the thermal power units around the nuclear power unit 1.

[0107] The nuclear power peak load regulation system of this embodiment may have the following beneficial effects:

[0108] During the peak load period of the nuclear power unit 1, the reactor 11 can operate at full power, and the high-temperature and high-pressure steam at the output end of the second steam generator 12, part of the steam extracted from the second high-pressure cylinder 13 and part of the steam extracted from the second medium- and low-pressure cylinders 14 are coupled with the heat pump unit 2 through the heat absorber 23, and the heat of the steam is "transferred" to the high-temperature energy storage medium by utilizing the advantages of the heat pump unit 2 itself (COP>1), and the heat is increased in value.

[0109] During peak hours of electricity consumption, the thermal energy stored in the heat pump unit 2 can be coupled with the boiler 31 in the superheated Rankine cycle unit 3 to jointly provide high-quality steam for the steam turbine and generate electricity, thereby improving the top load capacity of the coupled system.

[0110] The heat pump unit 2 uses common heat media for heat storage, and has the advantages of low cost and high energy storage density. In addition, the heat pump unit 2 is not restricted by geographical conditions. By coupling with the nuclear power unit 1 and the superheated Rankine cycle unit 3, it can provide better regulation capabilities for new energy power generation, ensure the safety and stability of the new power system, and bring corresponding economic benefits to the nuclear power plant while achieving positive social benefits.

[0111] In addition to participating in deep peak-shaving operation, the modified nuclear power unit 1 can also adapt to various other types of power auxiliary services, such as start-stop peak-shaving transactions, rotating reserve transactions, and emergency short-term peak-shaving transactions; in addition, it can also provide high-parameter industrial steam supply to the outside world and obtain considerable economic benefits.

[0112] It should be noted that, in the description of the present disclosure, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present disclosure, unless otherwise specified, the meaning of "plurality" is two or more.

[0113] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present disclosure includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present disclosure belong.

[0114] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0115] Although the embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A nuclear power peak-shaving system coupled with heat pump energy storage, characterized in that: include: Nuclear power units, heat pump units and superheated Rankine cycle units; Wherein, the nuclear power unit has a first steam circulation path and uses saturated steam in the first steam circulation path to generate electricity, and the superheated Rankine cycle unit has a second steam circulation path and uses superheated steam in the second steam circulation path to generate electricity; The heat pump unit includes: a compression device and an expansion device. The passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the first steam circulation passage when in a peak shaving state, and the passage between the output end of the compression device and the input end of the expansion device is used to release heat to the second steam circulation passage when in a peak state.

2. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 1, characterized in that: The heat pump unit also includes: A heat absorber, wherein a heat release channel of the heat absorber is connected in parallel to the first steam circulation path, and the heat absorption channel of the heat absorber is connected in series between the input end of the compression device and the output end of the expansion device, the input end of the heat absorption channel of the heat absorber is connected to the output end of the expansion device, and the output end of the heat absorption channel of the heat absorber is connected to the input end of the compression device; A heat release device, wherein the heat release channel of the heat release device is connected in series between the output end of the compression device and the input end of the expansion device, and the heat release channel input end of the heat release device is connected to the output end of the compression device, the heat release channel output end of the heat release device is connected to the input end of the expansion device, and the heat absorption channel of the heat release device is connected in parallel to the second steam circulation path.

3. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 2 is characterized in that: The heat pump unit also includes: A low temperature tank, the output end of which is connected to the input end of the heat absorption channel of the radiator; A high temperature tank, the input end of which is connected to the output end of the heat absorption channel of the radiator; A first steam generator, wherein an input end of a heat release channel of the first steam generator is connected to an output end of the high temperature tank, and an output end of a heat release channel of the first steam generator is connected to an input end of the low temperature tank, and a heat absorption channel of the first steam generator is connected in parallel to a main steam heating channel in the second steam circulation channel; A reheater, wherein the input end of the heat release channel of the reheater is connected to the output end of the high-temperature tank, and the output end of the heat release channel of the reheater is connected to the input end of the low-temperature tank, and the heat absorption channel of the reheater is connected in parallel with the reheat steam heating channel in the second steam circulation channel.

4. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 3 is characterized in that: The superheated Rankine cycle unit comprises: A boiler, a first high-pressure cylinder, a first medium- and low-pressure cylinder, and a first generator; Wherein, the first high-pressure cylinder, the first medium- and low-pressure cylinders and the first generator are sequentially connected in transmission; The input end of the first high-pressure cylinder is respectively connected to the output end of the main steam heating passage of the boiler and the output end of the heat absorption passage of the first steam generator, and the first output end of the first high-pressure cylinder is respectively connected to the input end of the reheat steam heating passage of the boiler and the input end of the heat absorption passage of the reheater; The input end of the first intermediate and low pressure cylinder is respectively connected to the output end of the reheat steam heating passage of the boiler and the output end of the heat absorption passage of the reheater, and the first output end of the first intermediate and low pressure cylinder is respectively connected to the input end of the main steam heating passage of the boiler and the input end of the heat absorption passage of the first steam generator.

5. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 4 is characterized in that: The superheated Rankine cycle unit further comprises: a first condenser, a first low-pressure heater, a first deaerator, and a first high-pressure heater; The input end of the first condenser is connected to the first output end of the first intermediate and low pressure cylinder, the output end of the first condenser is connected to the input end of the heat absorption channel of the first low pressure heater, and the input end of the heat release channel of the first low pressure heater is connected to the second output end of the first intermediate and low pressure cylinder; The input end of the first deaerator is respectively connected to the output end of the heat absorption channel of the first low-pressure heater, the output end of the heat release channel of the first low-pressure heater and the third output end of the first medium- and low-pressure cylinders, and the output end of the first deaerator is connected to the input end of the heat absorption channel of the first high-pressure heater; The heat release channel input end of the first high-pressure heater is connected to the second output end of the first high-pressure cylinder, and the heat release channel output end and the heat absorption channel output end of the first high-pressure heater are respectively connected to the main steam heating passage input end of the boiler and the heat absorption channel input end of the first steam generator.

6. The nuclear power peak-shaving system coupled with heat pump energy storage according to any one of claims 1 to 5, characterized in that: The first steam circulation path comprises: A primary circuit and a secondary circuit, wherein the primary circuit is used to release heat to the secondary circuit; Wherein, the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the primary circuit and / or the secondary circuit when in the peak load regulation state.

7. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 6, characterized in that: The nuclear power unit comprises: reactor and second steam generator; The output end of the reactor is connected to the input end of the heat release channel of the second steam generator, and the input end of the reactor is connected to the output end of the heat release channel of the second steam generator, and the heat absorption channel of the second steam generator is connected in series in the secondary circuit; The loop is formed between the heat release channels of the reactor and the second steam generator, and the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the passage between the output end of the reactor and the input end of the reactor when in peak shaving state.

8. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 7, characterized in that: The nuclear power plant unit also includes: a second high-pressure cylinder, a second intermediate-low-pressure cylinder, a heat exchanger, and a second generator; Wherein, the second high-pressure cylinder, the second medium- and low-pressure cylinders and the second generator are sequentially connected in transmission; The input end of the second high-pressure cylinder and the input end of the heat release channel of the heat exchanger are respectively connected to the output end of the heat absorption channel of the second steam generator, and the first output end of the second high-pressure cylinder is connected to the input end of the heat absorption channel of the heat exchanger; The input end of the second intermediate and low pressure cylinder is connected to the output end of the heat absorption channel of the heat exchanger, and the first output end of the second intermediate and low pressure cylinder is connected to the input end of the heat absorption channel of the second steam generator; The second circuit is formed between the second high-pressure cylinder, the second intermediate and low-pressure cylinders and the heat exchanger, and the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the output end of the heat absorption channel of the second steam generator, the second output end of the second high-pressure cylinder and the second output end of the second intermediate and low-pressure cylinders when in the peak shaving state.

9. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 8, characterized in that: The nuclear power plant unit also includes: An ejector and a temperature reduction and pressure reduction device, wherein a first input end of the ejector is connected to an output end of a heat absorption channel of the second steam generator, and a second input end of the ejector is connected to a second output end of the second high-pressure cylinder, a third input end of the ejector is connected to a second output end of the second medium- and low-pressure cylinder, an output end of the ejector is connected to an input end of the temperature reduction and pressure reduction device, and an output end of the temperature reduction and pressure reduction device is connected to an input end of a heat absorption channel of the second steam generator; Wherein, the passage between the input end of the compression device and the output end of the expansion device is used to absorb heat from the passage between the output end of the ejector and the input end of the temperature and pressure reduction device when in the peak shaving state.

10. The nuclear power peak-shaving system coupled with heat pump energy storage according to claim 9, characterized in that: The nuclear power plant unit also includes: a second condenser, a second low-pressure heater, a second deaerator, and a second high-pressure heater; The input end of the second condenser is connected to the first output end of the second intermediate and low pressure cylinder, the output end of the second condenser is connected to the input end of the heat absorption channel of the second low pressure heater, and the input end of the heat release channel of the second low pressure heater is connected to the third output end of the second intermediate and low pressure cylinder; The input end of the second deaerator is respectively connected to the output end of the heat absorption channel of the second low-pressure heater, the output end of the heat release channel of the second low-pressure heater, the first output end of the second high-pressure cylinder and the output end of the temperature reduction and pressure reduction device, and the output end of the second deaerator is connected to the input end of the heat absorption channel of the second high-pressure heater; The heat release channel input end of the second high-pressure heater is respectively connected to the third output end of the second high-pressure cylinder and the heat release channel output end of the heat exchanger, and the heat release channel output end and the heat absorption channel output end of the second high-pressure heater are respectively connected to the heat absorption channel input end of the second steam generator.

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