Floating nuclear power generation system

Abstract

This application discloses a floating nuclear power generation system with a more robust emergency power supply system. [Solution] A floating nuclear power generation system comprising a reactor, a turbine generator driven by steam generated by the heat of the reactor, a floating body on which the reactor and turbine generator are arranged and which is moored at sea, and a floating power supply system having an emergency system capable of supplying power to predetermined equipment for cooling the reactor in an emergency, and a normal system capable of supplying power to equipment not connected to the emergency system, wherein a normal power generation facility that generates electricity using natural energy is connected to the emergency system.

Description

Technical Field

[0001] The present invention relates to a floating nuclear power generation system.

Background Art

[0002] A nuclear power generation system is equipped with an emergency power source for maintaining the cooling function of the nuclear reactor even when the external power source is lost. For example, Patent Document 1 proposes using a wind power generation device as the emergency power source of a nuclear power plant.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a nuclear power generation system is floated on the sea, a submarine cable for electrically connecting the floating body and the onshore power grid for power transmission needs to be laid. Such a submarine cable connected to the onshore power grid is positioned as an external power source when viewed from the nuclear power generation system side. Therefore, when preparing an emergency power source for such a floating nuclear power generation system, it is natural to provide the emergency power source on the floating body.

[0005] In addition, the power supply system of a nuclear power generation system generally has an emergency system for supplying power to important facilities related to safety and a normal system for supplying power to normal facilities that do not immediately affect safety even if they become inoperable. When the external power source is lost, basically, the emergency power source only supplies power to the emergency system. Therefore, when the nuclear power generation system is made floating, the power source outside the floating body is positioned as a normal power source, and it is difficult to preferentially supply power from the power source outside the floating body to the emergency system rather than the normal system.

[0006] Therefore, this application discloses a floating nuclear power generation system with a more robust emergency power supply system. [Means for solving the problem]

[0007] To solve the above problems, the present invention connects a regular power generation facility that generates electricity using natural energy to an emergency power system that can supply power to a predetermined facility for cooling a nuclear reactor in an emergency.

[0008] More specifically, the present invention relates to a floating nuclear power generation system comprising: a nuclear reactor; a turbine generator driven by steam generated by the heat of the nuclear reactor; a floating body on which the nuclear reactor and turbine generator are arranged and which is moored at sea; and a floating power supply system having an emergency system capable of supplying power to predetermined equipment for cooling the nuclear reactor in emergency situations, and a regular system capable of supplying power to equipment not connected to the emergency system, wherein a regular power generation facility that generates electricity using natural energy is connected to the emergency system.

[0009] The above-mentioned regular power generation equipment generates electricity using renewable energy, and therefore can generate electricity both under normal conditions and in the event of a loss of external power. For this reason, if such regular power generation equipment is connected to the emergency grid, it is possible to cover part or all of the floating nuclear power generation system's self-consumption with the electricity from the regular power generation equipment during normal conditions, and to supply power from the regular power generation equipment to the emergency grid in the event of a loss of external power. Therefore, with such a floating nuclear power generation system, The emergency power supply system is more robust.

[0010] Furthermore, the emergency power system may be connected to the regular power generation equipment located on or near the floating structure. If the regular power generation equipment is located on or near the floating structure, it is possible to more reliably supply power from the regular power generation equipment to the emergency power system in the event of a loss of external power compared to when the regular power generation equipment is located far away from the floating structure.

[0011] Furthermore, the regular power generation equipment consists of offshore wind power generation equipment positioned around the floating body, and the offshore wind power generation equipment may be connected to the emergency power system by cables running along the seabed. If the emergency power system and the offshore wind power generation equipment are connected by cables running along the seabed, these cables will not interfere with the floating body.

[0012] Furthermore, the system may be equipped with an emergency generator capable of supplying power to the emergency power grid in times of emergency. Under normal circumstances, the emergency power grid can supply power from the regular power generation equipment to the regular power grid via the emergency power grid. In times of emergency, by being disconnected from the regular power grid, the emergency generator and the regular power generation equipment may supply power only to designated equipment. This means that in the event of a loss of external power, the regular power generation equipment and the emergency generator can work together to supply power to the emergency power grid. Therefore, it can be said that such a floating nuclear power generation system has a more robust emergency power supply system. [Effects of the Invention]

[0013] In the case of the floating nuclear power generation system described above, the emergency power supply system is more robust. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram showing the equipment layout of a floating nuclear power generation system according to an embodiment. [Figure 2] Figure 2 is a schematic diagram showing the system configuration of a floating nuclear power generation system according to an embodiment. [Figure 3] Figure 3 is a single-line diagram illustrating the schematic power supply system within the floating structure. [Figure 4] Figure 4 shows a first example of a wind power generation facility installation method. [Figure 5] Figure 5 shows a second example of a wind power generation facility installation method. [Figure 6] Figure 6 shows a third example of a wind power generation facility installation method. [Modes for carrying out the invention]

[0015] Hereinafter, embodiments of the present invention will be described. The embodiments shown below are one aspect of the present invention and do not limit the technical scope of the present invention.

[0016] <Overview of Equipment Arrangement> FIG. 1 is a schematic diagram showing the equipment arrangement of the floating nuclear power generation system 1 according to the embodiment. In FIG. 1(A), the layout of various devices provided in the floating nuclear power generation system 1 is shown when viewed from above. In FIG. 1(B), the layout of various devices provided in the floating nuclear power generation system 1 is shown when viewed from the side.

[0017] The floating nuclear power generation system 1 is a floating power generation system that can be floated on the sea. For this reason, the floating nuclear power generation system 1 includes a floating body 2. As can be seen from FIG. 1(A), the floating body 2 has a streamlined shape. However, the floating body 2 is not a ship intended for autonomous navigation on the sea. The floating body 2 floats in a moored state on the sea in order to transmit the power generated by the floating nuclear power generation system 1 to the land. And, in order to suppress the resistance against the tidal current, only one end in the longitudinal direction of the floating body 2 is moored, and the other end floats on the sea in an unmoored state. For this reason, the floating body 2 floats on the sea like a drift. That is, when the floating body 2 receives the tidal current, it floats on the sea in a posture where the moored part naturally faces the upstream side of the tidal current.

[0018] Since the floating body 2 has such a streamlined shape, in the present embodiment, for convenience, the moored part in the longitudinal direction of the floating body 2 is referred to as the "bow side", and the unmoored part is referred to as the "stern side". Therefore, in FIG. 1, the left side of the paper is the "bow side" and the right side of the paper is the "stern side". Also, for FIG. 1(B), the internal configuration of the floating nuclear power generation system 1 when viewed from the left side of the floating body 2 will be shown.

[0019] In addition, in this embodiment, the streamlined floating body 2 is exemplified, but the floating body 2 may be a non-streamlined floating body. As the floating body 2 used in the floating nuclear power generation system 1, for example, a cylindrical floating body having a circular shape in plan view, a rectangular parallelepiped floating body having a rectangular shape in plan view, or floating bodies of various other shapes may be used.

[0020] As shown in FIG. 1, the floating nuclear power generation system 1 includes a nuclear reactor 3 disposed near the central portion of the floating body 2 and a turbine generator 4 disposed on the bow side of the nuclear reactor 3. The nuclear reactor 3 generates steam by boiling water with the heat generated by nuclear fission. The turbine generator 4 generates electricity by rotating the generator with a steam-driven turbine. In this embodiment, a floating nuclear power generation system 1 of a boiling water reactor (BWR) that drives the turbine generator 4 with the steam of the nuclear reactor 3 is exemplified, but the floating nuclear power generation system 1 may be, for example, a pressurized water reactor (PWR), or may use various other systems.

[0021] The floating nuclear power generation system 1 is equipped with various equipment in addition to the floating body 2, reactor 3, and turbine generator 4 described above. For example, the floating nuclear power generation system 1 has reactor equipment areas 5 and 7, a pit 6, and a fuel pool 8 around the reactor 3. The floating nuclear power generation system 1 also has a desalination plant 9, an IC / PCCS pool 10, various equipment areas 12, a living area 13, and a waste treatment room 24 located aft of the reactor 3. The floating nuclear power generation system 1 also has a condensate storage tank 14 located between the reactor 3 and the turbine generator 4. The floating nuclear power generation system 1 also has a laydown area 18 and an ancillary equipment area 19 located near the bow of the floating body 2. The ancillary equipment area 19 is equipped with a main transformer 20 and an auxiliary boiler 21. The floating nuclear power generation system 1 also has a diesel fuel tank 23 on the deck near the bow of the floating body 2. Furthermore, the floating nuclear power generation system 1 is equipped with a bow ballast tank 25, a bottom ballast tank 26, a stern ballast tank 27, and side ballast tanks 28 for controlling the attitude of the floating body 2.

[0022] Reactor equipment areas 5 and 7 house various reactor equipment installed outside the containment vessel of reactor 3. Equipment located in reactor equipment areas 5 and 7 includes, for example, pumps and valves for various reactor cooling systems such as the emergency core cooling system and residual heat removal system, pumps and valves for the pool water cooling system that cools the fuel pool, compressed air control equipment, ventilation and air conditioning equipment, emergency diesel generators that serve as emergency power sources, DC power supply equipment using batteries, and various other equipment.

[0023] Pit 6 is a pit used to temporarily store various items during periodic inspections and fuel changes. Examples of items to be placed in Pit 6 include steam separators and steam dryers that are located above the nuclear fuel inside Reactor 3.

[0024] Fuel pool 8 is a pool for storing unused or spent nuclear fuel. The nuclear fuel of reactor 3 is in the form of fuel assemblies. Therefore, fuel pool 8 is equipped with racks to hold the fuel assemblies at appropriate intervals from each other. In addition, a fuel exchange machine is installed at the top of fuel pool 8 for transferring fuel assemblies between reactor 3 and fuel pool 8.

[0025] The desalination plant 9 is a device that desalinates seawater. Since the floating nuclear power generation system 1 is used while floating on the sea, it is not possible to obtain fresh water with almost no salt content from rivers, as is the case with land-based facilities. For this reason, the floating nuclear power generation system 1 is equipped with a desalination plant 9 to desalinate seawater by removing salt in order to secure reactor cooling water and various other types of water. Various methods such as reverse osmosis and evaporation can be applied as desalination methods to the desalination plant 9.

[0026] IC / PCCS pool 10 houses IC heat exchangers and PCCS heat exchangers. The IC heat exchangers are emergency condenser (IC: Isolation Condenser) equipment and are powered by AC power. In the event of a loss of power or other incident that isolates the containment vessel, reactor 3 is cooled. The PCCS heat exchanger is part of the Passive Containment Cooling System (PCCS) and cools the steam released into the containment vessel during severe accidents, etc.

[0027] The various equipment area 12 includes a central control room for operating the floating nuclear power generation system 1, an access control room for managing entry and exit to the radiation controlled area, and various other facilities. Note that the aforementioned emergency diesel generators and DC power supply equipment may be located in the various equipment area 12 rather than in the reactor equipment areas 5 and 7.

[0028] The residential area 13 will be equipped with living facilities for operators and other personnel staying at the floating nuclear power generation system 1. These living facilities will include, for example, private rooms with beds, a dining room equipped with cooking appliances, bathing facilities, recreational facilities, and various other facilities.

[0029] The waste treatment room 24 is equipped with various facilities for processing radioactive waste. Examples of radioactive waste processed in the waste treatment room 24 include liquid waste such as wastewater generated in radiation-controlled areas, and miscellaneous solid waste such as waste materials generated in connection with various operations. These wastes are reduced in volume in the waste treatment room 24 by evaporation, concentration, compression, or incineration, and then stored in the floating body 2 before being transported out of the floating body 2.

[0030] The condensate storage tank 14 is a tank that stores water that can be supplied to the reactor 3. The condensate storage tank 14 is connected to the condenser of the turbine generator 4 and the emergency core cooling system, and is used for supplying water to the condenser during normal operation and for injecting water into the reactor 3 in emergencies.

[0031] The laydown area 18 is a workspace for disassembling and inspecting various large pieces of equipment, such as the turbine generator 4. The laydown area 18 is on the same floor as the operating floor of the turbine generator 4, and large pieces of equipment can be easily moved using the crane equipment installed above the operating floor.

[0032] The ancillary equipment area 19 houses various ancillary equipment, such as the main transformer 20 and the auxiliary boiler 21. The main transformer 20 is a transformer that boosts the electricity generated by the turbine generator 4 to the voltage of the power grid. The auxiliary boiler 21 is a boiler that generates steam using the heat produced by burning light oil.

[0033] The floating nuclear power generation system 1 is moored to the sea by an anchor chain 22 installed on the bow side of the floating body 2. As mentioned above, when the floating nuclear power generation system 1 is subjected to tidal currents, it floats on the sea with the moored portion naturally facing upstream of the current. For this reason, the submarine cable connecting the floating nuclear power generation system 1 to the onshore power grid is suspended from near the bow of the floating body 2 toward the seabed, similar to the anchor chain 22. For this reason, it is rational for the main transformer 20, which boosts the electricity generated by the turbine generator 4 to the voltage of the power grid, to be located near the bow of the floating body 2, close to the submarine cable, as shown in Figure 1. ru.

[0034] Furthermore, the auxiliary boiler 21 is used during the startup of the floating nuclear power generation system 1 to provide steam for the turbine generator 4's ground and to heat the steam equipment around the turbine. For this reason, it is reasonable to place the auxiliary boiler 21 near the turbine generator 4.

[0035] Therefore, the floating nuclear power generation system 1 adopts a configuration in which the main transformer 20 and auxiliary boiler 21 are located in an ancillary equipment area 19 provided on the bow side of the floating body 2. In addition, the floating nuclear power generation system 1 adopts a configuration in which a diesel fuel tank 23 for storing diesel fuel supplied to the auxiliary boiler 21 is located above the ancillary equipment area 19. The ancillary equipment area 19 contains not only the main transformer 20 and auxiliary boiler 21, but also switching equipment such as disconnectors (LS: Line Switches) for opening and closing the electrical connection between the submarine cable and the main transformer 20. Even if it is installed.

[0036] The bow ballast tank 25, bottom ballast tank 26, stern ballast tank 27, and side ballast tanks 28 are tanks for receiving ballast water to control the attitude of the floating body 2. The ballast water in the bow ballast tank 25, bottom ballast tank 26, and stern ballast tank 27 can also be used as seawater to cool the reactor 3 in the event of an emergency of the floating nuclear power generation system 1. The water in the bow ballast tank 25, bottom ballast tank 26, and stern ballast tank 27 can be naturally injected using the water pressure of the seawater by opening an intake port provided on the bottom of the floating body 2, for example. Pumps may also be used in conjunction with the water injection as needed. Drainage from the bow ballast tank 25, bottom ballast tank 26, and stern ballast tank 27 can be performed using pumps or ejectors.

[0037] The above outline describes the equipment layout of the floating nuclear power generation system 1 according to this embodiment. However, the above equipment layout is merely an example, and other equipment layouts may be adopted. Next, the outline of the system configuration of the floating nuclear power generation system 1 will be described.

[0038] <Overview of System Structure> Figure 2 is a schematic diagram showing the system configuration of a floating nuclear power generation system 1 according to an embodiment. The floating nuclear power generation system 1 mainly consists of a reactor system R and a turbine system T. The aforementioned reactor 3 is the main component of the reactor system R. The aforementioned turbine generator 4 is the main component of the turbine system T.

[0039] The reactor system R, which includes reactor 3, is equipped with various facilities such as a containment vessel 3A, nuclear fuel 3B, control rods 3C, recirculation pump 3D, and pressure vessel 3E. The turbine system T, which includes turbine generator 4, is equipped with various facilities such as a condenser 4C, circulating water piping 4D, circulating water pump 4E, and feedwater pump 4F, in addition to the turbine 4A and generator 4B that make up turbine generator 4.

[0040] The containment vessel 3A is a vessel that houses the pressure vessel 3E containing the nuclear fuel 3B, etc., and plays the role of containing radioactive materials released from the pressure vessel 3E in the event of a meltdown accident of the reactor 3. The containment vessel 3A may be made of concrete or of the steel materials that make up the floating body 2. The containment vessel 3A encloses the pressure vessel 3E containing the reactor 3 in its center, and has an upper drywell 3M above the pressure vessel 3E and a lower drywell 3N below the pressure vessel 3E. The containment vessel 3A also has a suppression pool 3H around the lower drywell 3N.

[0041] The pressure vessel 3E is a container that encloses nuclear fuel 3B, etc., and is used to cool the reactor 3 with water and It serves to contain the steam. In the center of the pressure vessel 3E, hundreds of nuclear fuel assemblies 3B are arranged to form the main body of the reactor 3. Control rods 3C, which can move up and down by a drive mechanism located at the bottom of the pressure vessel 3E, are inserted into the gaps between the fuel assemblies in the main body of the reactor 3. When the control rods 3C are withdrawn from the reactor 3 and the reactor 3 reaches a critical state, the reactor 3 continuously generates heat. When the control rods 3C are inserted into the reactor 3 and the reactor 3 reaches a subcritical state, the heat generated by the reactor 3 gradually decreases.

[0042] A recirculation pump 3D is provided in the pressure vessel 3E. The recirculation pump 3D is responsible for heat removal and control of the reactor output of the reactor 3 by forcibly circulating water, which is the reactor coolant, in the liquid phase portion within the pressure vessel 3E. In this embodiment of the floating nuclear power generation system 1, an Advanced Boiling Water Reactor (ABWR) is assumed, and therefore in Figure 2, the recirculation pump 3D is shown to be installed in the pressure vessel 3E. However, the floating nuclear power generation system 1 is not limited to this configuration. For example, the floating nuclear power generation system 1 may have a recirculation system in which the recirculation pump and circulation piping are arranged outside the pressure vessel 3E.

[0043] A main steam pipe 3L is connected to the pressure vessel 3E to send steam generated within the pressure vessel 3E to the turbine generator 4 of the turbine system T. Since the main steam pipe 3L is a pipe connecting the inside and outside of the containment vessel 3A, main steam isolation valves 3J and 3K are provided near the penetration point of the containment vessel 3A to allow for the isolation of the containment vessel 3A. A relief safety valve 3F is provided in the middle of the main steam pipe 3L to prevent the internal pressure of the pressure vessel 3E from becoming excessive when the main steam isolation valves 3J and 3K are closed. The end of the exhaust pipe 3G, located downstream of the relief safety valve 3F, is located in the suppression pool 3H.

[0044] The turbine 4A and generator 4B, which make up the turbine generator 4, are connected by the same rotating shaft. The turbine 4A has a structure in which the impeller is housed within a casing. Below the turbine 4A, a condenser 4C is provided to condense the steam that has passed through the turbine 4A. Inside the condenser 4C, there are many thin tubes that form part of the path of the circulating water piping 4D, which connects the intake and discharge ports located below the waterline on the outer surface of the floating body 2. The steam is condensed by the cold heat of seawater supplied by the circulating water pump 4E, which is located along the path of the circulating water piping 4D. As a result, the pressure difference between the steam supplied from the reactor 3 through the main steam pipe 3L and the inside of the condenser 4C applies power to the impeller to rotate the generator 4B. This causes the generator 4B to rotate and generate electricity. The condensed water inside the condenser 4C is then supplied back into the pressure vessel 3E via the feedwater piping 4G by the feedwater pump 4F.

[0045] Note that Figure 2 only shows a schematic of the reactor system R and turbine system T, and in reality, a wide variety of equipment is installed. For example, important equipment such as steam control valves and turbine bypass valves are installed near turbine 4A in the main steam pipe 3L. The turbine bypass valve may be capable of 100% bypass, sending the entire amount of main steam at rated output directly to condenser 4C without passing through turbine 4A, or it may have a lower bypass capacity. Also, important equipment such as feedwater flow control valves, condensate demineralizers, and feedwater heaters are installed in the feedwater piping 4G. In addition, piping for the emergency core cooling system is installed inside and outside the containment vessel 3A. Furthermore, turbine 4A is a combination of a high-pressure turbine and multiple low-pressure turbines.

[0046] Furthermore, although Figure 2 shows only one system for each piece of equipment, each piece of equipment in the floating nuclear power generation system 1 is redundant. For example, multiple circulating water pumps 4E and feedwater pumps 4F are provided.

[0047] In reactor system R, the position of control rods 3C is adjusted so that reactor 3 maintains a predetermined reactor output. In addition, in the turbine system T, the opening of the steam control valve is adjusted so that the turbine generator 4 maintains a predetermined rotational speed, and the feedwater flow rate of the feedwater pump 4F is adjusted so that the reactor 3 maintains a predetermined water level. With this configuration, the floating nuclear power generation system 1 transmits the thermal energy generated by the nuclear reaction of the reactor 3 as electrical energy to the power grid through the generator 4B, which is synchronized with the grid frequency.

[0048] The general configuration of the floating nuclear power generation system 1 according to this embodiment is as described above. Next, the power supply system of the floating nuclear power generation system 1 will be described. Figure 3 is a single-line diagram showing a schematic of the power supply system within the floating structure 2.

[0049] The power supply system within a floating nuclear power generation system is mainly divided into a normal system and an emergency system. The emergency system is a system that can be supplied by emergency generators in the event of a loss of external power. For this reason, critical equipment related to safety is connected to the emergency system. On the other hand, the normal system is a system that will experience a power outage in the event of a loss of external power. For this reason, normal equipment that will not immediately impair safety even if it becomes inoperable is connected to the normal system.

[0050] Specifically, as shown in Figure 3, in the power supply system within the floating nuclear power generation system 1, among the 6.9kV AC busbars, M / C (Metal Clad), M / C A-1, A-2, B-1, and B-2 belong to the normal system, while M / CC, D, E, and F belong to the emergency system. In addition, among the 480V AC busbars, P / C (Power Center), P / CC located under the M / CC belong to the emergency system, while the other P / Cs belong to either the normal system or the emergency system, corresponding to the higher-level M / Cs.

[0051] As shown in Figure 3, critical equipment connected to emergency systems such as M / CC and P / CC includes various pieces of equipment such as the residual heat removal system (RHR), reactor auxiliary cooling system (RCW), control rod drive mechanisms (CRD, FMCRD), reactor auxiliary cooling seawater system (RSW), ventilation and air conditioning auxiliary emergency cooling water system (HECW), DC 125V chargers, IA (control air) compressors, and other equipment. Equipment such as the residual heat removal system and reactor auxiliary cooling system are essential not only during operation but also for maintaining the cooling capacity of the reactor when it is shut down, and are therefore important equipment that must operate even immediately after a reactor scram accompanied by a loss of external power.

[0052] On the other hand, as shown in Figure 3, normal equipment connected to the operating system such as M / C A-1 includes various pieces of equipment such as feedwater pumps (FWP), high-pressure condensate pumps (HPCP), low-pressure condensate pumps (LPCP), turbine auxiliary cooling systems (TCW), and recirculation pumps (RIP), as well as other equipment. While it is desirable for equipment such as feedwater pumps and high-pressure condensate pumps to be in an operational state at all times, they are not necessarily required to be operational immediately after a reactor scram accompanied by a loss of external power. For example, since the cooling capacity of the main condenser is higher than that of the emergency core cooling system (ECCS), it is desirable from the standpoint of ensuring reactor cooling capacity for condensate-related equipment such as circulating water pumps and feedwater pumps to be in operation. However, because condensate-related equipment such as circulating water pumps and feedwater pumps consume a large amount of power, it is not practical to power them with emergency power, and the emergency core cooling system (ECCS) is designed to sufficiently cool the reactor core C. Therefore, in the floating nuclear power generation system 1, these facilities are connected to the normal power grid, and in the event of a loss of external power, the connection between the emergency power grid and the normal power grid is released by a circuit breaker, so that even with only the emergency power supply, which has limited output, the power of the emergency power grid can be supplied in the event of a loss of external power.

[0053] There are several possible routes for supplying power to the power grid within the floating nuclear power generation system 1. The first pattern is, for example, the pattern when the floating nuclear power generation system 1 is not generating power, and power is supplied through transmission lines (Line 1, Line 2) that connect to the land power grid via submarine cables, and through the starting transformers (A-STr, BS). One pattern involves supplying power to each M / C via a transformer (Tr). In Figure 3, a 275kV transmission line is used as an example, so the starting transformer will step down 275kV to 6.9kV. In the first pattern, power may be received from both Line 1 and Line 2, or power may be received from only one of them due to maintenance and inspection of the transmission line, etc.

[0054] The second pattern is, for example, the pattern when power is being generated by the floating nuclear power generation system 1. In this pattern, power is transmitted from the main generator MGe of the turbine system T to the transmission lines (Line 1, Line 2) via the main transformer MTr, while a portion of the power from the main generator MGe is supplied to each M / C via the in-house transformers (A-HTr, B-HTr). In Figure 3, a 27kV main generator MGe is used as an example, so the main transformer will step up from 27kV to 275kV, and the in-house transformers will step down from 27kV to 6.9kV. In this pattern, if the turbine generator 4 can completely bypass the main steam (100% bypass operation), power may not be transmitted to the transmission lines (Line 1, Line 2), and all of the power from the main generator MGe may be supplied to each M / C via the in-house transformers (A-HTr, B-HTr).

[0055] The third pattern is, for example, a situation where external power is lost due to a system fault on the transmission line (Line 1, Line 2), and in a typical nuclear power plant, this pattern involves directly supplying power from the emergency power source, the diesel generator (DG), to the M / C of the emergency system. In a typical nuclear power plant, if the voltage of the M / C of the emergency system drops, in the case of the M / CC illustrated in Figure 3, when the voltage of the M / CC drops, the diesel generator (DG connected to the M / CC) immediately starts up automatically and begins supplying power to the M / CC. However, in the floating nuclear power generation system 1 of this embodiment, in addition to power supply by the diesel generator, it is also possible to supply power to the emergency system from normal power generation equipment that generates power from renewable energy.

[0056] In other words, in the floating nuclear power generation system 1, as illustrated by the "*" in Figure 3, wind power generation equipment (WTG) and solar power generation equipment (PV) are connected to each M / CC, D, E, and F in addition to the diesel generator (DG). Furthermore, each M / CC, D, E, and F is equipped with a connection port for an external power supply (EXP). The connection port for the external power supply is provided, for example, in the event that the floating nuclear power generation system 1 experiences a power outage, and is used to receive power from other ships moored to the floating body 2.

[0057] The frequency of the AC power generated by the wind turbine (WTG) varies depending on the rotational speed of the wind turbine and the gear ratio of the transmission. Similarly, the voltage and current of the DC power generated by the photovoltaic (PV) system vary depending on the amount of sunlight incident on the solar panels. Therefore, in this embodiment, a large battery storage system P3 is installed in the circuit connecting the M / C busbar to the photovoltaic (PV) converter P1 and the wind turbine (WTG) converter P2, and AC power is supplied from the battery storage system P3 to the M / C busbar via the inverter P4.

[0058] Wind power generation equipment and solar power generation equipment are facilities that generate electricity using natural energy, and therefore generate electricity not only in emergencies but also during normal times. Therefore, in the floating nuclear power generation system 1 according to this embodiment, by directly connecting the wind power generation equipment and solar power generation equipment to each M / CC, D, E, F of the emergency grid, during normal times, part or all of the self-consumption of the floating nuclear power generation system 1 is covered by the power of the wind power generation equipment and solar power generation equipment. Furthermore, if the normal grid experiences a power outage due to a loss of external power, the wind power generation equipment and solar power generation equipment connected to each M / CC, D, E, F of the emergency grid will supply power to the M / C of the emergency grid as an emergency power source via the battery storage equipment P3. Therefore, as long as at least one of the wind power generation equipment and solar power generation equipment is generating electricity, or as long as there is remaining charge in the battery storage equipment P3, it is possible to continue supplying power to the M / C of the emergency grid even if external power is lost. Even if both photovoltaic power generation facilities stop generating power, and the battery storage facility P3 loses its charge, the diesel generator, which detects a drop in the voltage of the M / C on the emergency grid and provides power, can continue to maintain the supply of power to the M / C on the emergency grid.

[0059] The storage capacity of the tanks for diesel fuel (diesel oil) used in diesel generators is limited. Therefore, if an external power outage continues for an unexpectedly long period, there is a risk of fuel depletion. In this respect, with the floating nuclear power generation system 1 according to this embodiment, renewable energy power generation equipment, such as wind power generation equipment and solar power generation equipment, which do not require fuel, are connected to the M / C of the emergency power grid, and furthermore, a battery storage system P3 is provided, so the possibility of a power outage in the emergency power grid due to the depletion of diesel generator fuel, which can occur in a normal nuclear power plant, can be suppressed as much as possible. In addition, with the floating nuclear power generation system 1 according to this embodiment, the normally used power generation equipment, such as wind power generation equipment and solar power generation equipment, which generate power during normal times, are connected to the M / C of the emergency power grid via the battery storage system P3, so even if an external power outage occurs, it is possible to prevent a temporary power outage in the M / C of the emergency power grid. Furthermore, with the floating nuclear power generation system 1 according to this embodiment, in addition to diesel generators that can supply the necessary power in the event of an emergency loss of external power, it is possible to use other power generation equipment such as wind power generation equipment and solar power generation equipment, making it easy to secure surplus power necessary to operate the equipment on the normal grid even in the event of an external power loss.

[0060] Furthermore, in this embodiment, a large battery storage system P3 is installed in the circuit connecting the emergency M / C busbar to the photovoltaic (PV) converter P1 and the wind turbine (WTG) converter P2. Therefore, under normal conditions (Pattern 1 and Pattern 2), the battery storage system P3 can be kept fully charged while supplying power generated by the wind turbine (WTG) and photovoltaic (PV) to electrical equipment inside and outside the floating nuclear power generation system 1. In addition, in the event of external power loss (Pattern 3), not only power from the diesel generator (DG) but also the stored power from the battery storage system P3 and the power generated by the wind turbine (WTG) and photovoltaic (PV) can be supplied to each load of the emergency M / C. For this reason, in this embodiment, the capacity of the battery storage system P3 is set as follows.

[0061] For example, if a loss-of-coolant accident (LOCA) occurs in a floating nuclear power plant system 1, and large pumps such as the high-pressure injection system of the emergency core cooling system (ECCS) are activated, the power consumed by the injection of water by these large pumps in the initial period (15 minutes from the onset of the accident) is estimated to be approximately 1.5 MWh (6 MW × 0.25 h) per system out of the four systems (C, D, E, F). Then, the power consumed by various emergency loads such as the residual heat removal system and auxiliary equipment cooling systems during continuous core cooling after the initial period is estimated to be approximately 110 MWh (1.5 MWh + 1505 kW × 72 h) per system out of the four systems (C, D, E, F), assuming that this occurs within 72 hours from the onset of the accident.

[0062] Therefore, in this embodiment, the storage capacity of one battery storage unit P3 is set to 118 MWh. By providing such battery storage units P3 in each M / CC, D, E, and F, the floating body 2 has a total battery storage capacity of 472 MWh. In this embodiment, having a battery storage system of this capacity within the floating body 2 makes it possible to cool the reactor core C for approximately 72 hours even if external power is lost and power from emergency diesel generators or renewable energy sources cannot be obtained.

[0063] Furthermore, it is preferable to install such a large-capacity battery storage system in a relatively spacious area within the floating body 2, such as below the turbine generator 4. Installing a large-capacity battery storage system in such a location makes it possible to shift the center of gravity of the floating body 2 from being biased towards the relatively heavy reactor 3 towards the turbine generator 4, thereby making the center of gravity of the floating body 2 more appropriate.

[0064] For such large-capacity battery storage systems, relatively safe battery storage systems such as lithium titanate secondary batteries are suitable. In the case of lithium titanate secondary batteries, there are off-the-shelf products standardized to the size of ship containers, with a total length of 7.5m, a total width of 2.5m, a total height of 3.5m, and a storage capacity of approximately 500kWh (weighing approximately 5.5t). To secure a total capacity of 472MWh with such off-the-shelf products, a total of 960 units of these products would be required. However, if a space with a total length of 120m, a total width of 70m, and a total height of 12m is secured, it is possible to store a total of 960 units (16 units in the total length direction for 120m, 20 units in the total width direction for 70m, and 3 units (3 levels) in the total height direction for approximately 12m), and such a space can be secured relatively easily below the turbine generator 4 within the floating body 2. Therefore, depending on the available space within the floating body 2, it is possible to install battery storage systems with even greater storage capacity. If a total of 960 battery units, each weighing approximately 5.5 tons, are placed below the turbine generator 4, the buoyancy of the floating body 2 can be slightly reduced. As a result, the floating body 2 will sink more than if such battery units were not installed, lowering its center of gravity and stabilizing its posture. Therefore, compared to the case where such battery units are not installed, the swaying of the floating body 2 will be suppressed, enabling stable operation of each component of the floating nuclear power generation system 1.

[0065] Furthermore, in light of charging battery storage systems of such capacity, it is preferable that solar power generation systems (PV) and wind power generation systems (WTG) also have a power generation capacity commensurate with the battery storage capacity. For example, if one of the four systems M / CC, D, E, and F has a solar power generation system (PV) with a power generation capacity of approximately 500 kW and a wind power generation system (WTG) with a power generation capacity of approximately 5 MW, this can be considered a power generation capacity commensurate with the battery storage capacity.

[0066] Furthermore, for example, if the battery capacity of battery storage system P3 is extremely small and the system configuration is such that it is better to use a diesel generator (DG) in conjunction with it in the event of a loss of external power, the diesel generator (DG) may be started simultaneously with the loss of external power, and the diesel generator (DG) may be operated in parallel with each of the M / CC, D, E, and F of the emergency system supplied by battery storage system P3. In this case, the inverter of battery storage system P3 and the automatic voltage regulator (AVR) and governor of the diesel generator will be adjusted so that the voltage and frequency of the M / C are at appropriate values.

[0067] Next, we will explain how to install wind power generation equipment.

[0068] <Example 1 of wind power generation facility layout> Figure 4 shows a first example of a method for installing wind power generation equipment. Figure 4(A) shows a top view of the floating body 2, and Figure 4(B) shows a side view of the floating body 2. As mentioned above, the floating body 2 is moored on the sea by an anchor chain 22 and therefore floats like a windsock. For this reason, the floating body 2 floats on the sea with its bow, which is moored by the anchor chain 22, naturally facing upstream of the current, and rotates around the mooring point by the anchor chain 22, as shown in Figure 4. Therefore, in this first example, the wind power generation equipment 101 is installed outside the rotation range of the wind power generation equipment 101. In Figure 4, the wind power generation equipment 101 is exemplified as a floating offshore wind power generation facility moored to the seabed by a cable, but the wind power generation equipment 101 may also be a bottom-fixed offshore wind power generation facility.

[0069] By installing the wind power generation equipment 101 in this manner, it is possible to easily install the wind power generation equipment 101 around the floating body 2. Furthermore, the floating body 2, which is moored by the anchor chain 22, will not come into contact with the wind power generation equipment 101.

[0070] In this first example, the power line connecting the M / C of the emergency power system and the wind power generation equipment 101 is suspended from the wind power generation equipment 101 to the seabed, with one end of the cable attached to the wind power generation equipment 101. The other end of the wire is suspended from the floating body 2 to the seabed along with the anchor chain 22 that moores the floating body 2. As a result, the power lines connecting the floating body 2 and the wind power generation equipment 101 do not interfere with the floating body 2 due to its rotation.

[0071] <Second example of wind power generation facility layout> Figure 5 shows a second example of a wind power generation facility installation method. Figure 5(A) shows a top view of the floating body 2, and Figure 5(B) shows a side view of the floating body 2. In this second example, the wind power generation facility 101 is connected to the stern side of the floating body 2. In Figure 5, two wind power generation facilities 101 are connected in series to the stern side of the floating body 2, but the number of wind power generation facilities 101 can be one or three or more. In this second example, the wind power generation facility 101 is limited to a floating type and is assumed not to be moored to the seabed.

[0072] The floating body 2 rotates around the mooring point by the anchor chain 22. However, since the rotation is performed by the current, if the floating wind power generation equipment 101, which is not moored to the seabed, is attached to the stern side of the floating body 2, the wind power generation equipment 101 will naturally be located downstream of the floating body 2. Therefore, the wind power generation equipment 101 does not obstruct the rotation of the floating body 2.

[0073] By installing the wind power generation equipment 101 in this manner, it is possible to easily install the wind power generation equipment 101 around the floating body 2. Furthermore, the floating body 2, which is moored by the anchor chain 22, will not come into contact with the wind power generation equipment 101. In addition, by releasing the mooring of the floating body 2 by the anchor chain 22 and towing the floating body 2 with a tugboat or the like, the wind power generation equipment 101 can be transported by sea together with the floating body 2.

[0074] In this first example, the power lines connecting the M / C of the emergency power system to the wind power generation equipment 101 are directly stretched between the floating body 2 and the wind power generation equipment 101 without passing over the seabed. As the floating body 2 rotates, the wind power generation equipment 101 moves in the same way, so the power lines connecting the floating body 2 and the wind power generation equipment 101 do not interfere with the floating body 2 or the wind power generation equipment 101.

[0075] <Third example of wind power generation facility layout> Figure 6 shows a third example of a wind power generation facility installation method. Figure 6(A) shows a top view of the floating body 2, and Figure 6(B) shows a side view of the floating body 2. In this third example, the wind power generation facility 101 is mounted on the floating body 2. In Figure 6, two wind power generation facilities 101 are mounted on the floating body 2, but the number of wind power generation facilities 101 may be one or three or more.

[0076] By installing the wind power generation equipment 101 in this manner, it is possible to easily connect the M / C of the emergency power grid to the wind power generation equipment 101. Furthermore, there is no need to install any floating structures for the wind power generation equipment 101 around the floating body 2. Therefore, the wind power generation equipment 101 does not affect the movement of the floating body 2 in any way.

[0077] <Other examples regarding the layout of power generation facilities> The installation method for wind power generation equipment is not limited to the three examples above. Wind power generation equipment may be installed in a form that appropriately combines the three examples above. Similarly, while solar power generation equipment may be installed on the sea as in the first and second examples of wind power generation equipment layouts, it is more rational to install it on the upper surface (deck) of the floating body 2 as in the third example of wind power generation equipment layout. [Explanation of symbols]

[0078] R...Reactor system: T...Turbine system: F...Floating float: C...Core: 1...Floating nuclear power generation system: 2...Floating float: 3...Reactor: 4...Turbine generator: 5...Reactor equipment area: 6...Pit: 7...Reactor equipment area: 8...Fuel pool: 9...Desalination plant :10··IC / PCCS Pool:12··Various Equipment Areas:13··Living Areas:14··Condensate Storage Tanks:18··Laydown Area:19··Ancillary Equipment Area:20··Main Transformer:21··Auxiliary Boiler:22··Anchor Chain:23··Diesel Fuel Tanks:24··Waste Treatment Room:25··Bow Ballast Tanks:26··Bottom Ballast Tanks:27··Stern Ballast Tanks:28··Side Ballast Tanks:3A··Containment Vessel:3B··Nuclear Fuel:3C··Control Rods:3D··Recirculation Pumps: 3E: Pressure vessel; 3F: Relief safety valve; 3G: Exhaust pipe; 3H: Suppression pool; 3J: Main steam isolation valve; 3K: Main steam isolation valve; 3L: Main steam pipe; 3M: Upper drywell; 3N: Lower drywell; 4A: Turbine; 4B: Generator; 4C: Condenser; 4D: Circulating water piping; 4E: Circulating water pump; 4F: Feedwater pump; 4G: Feedwater piping; 101: Wind power generation equipment; 102: Solar power generation equipment: P1, P2; Converter: P3: Battery storage equipment: P4: Inverter

Claims

1. Nuclear reactor and A turbine generator driven by steam generated by the heat of the aforementioned reactor, The aforementioned nuclear reactor and turbine generator are arranged on a floating body moored in the sea, The floating power supply system includes at least an emergency system capable of supplying power to designated equipment for reactor cooling in an emergency, and a normal system capable of supplying power to equipment not connected to the emergency system, The aforementioned emergency power system is connected to a regular power generation facility that generates electricity using renewable energy. Floating nuclear power generation system.

2. The emergency power system is connected to the regular power generation equipment located on or around the floating body. A floating nuclear power generation system according to claim 1.

3. The aforementioned regular power generation equipment is an offshore wind power generation facility located around the floating body, The aforementioned emergency system is connected to the aforementioned offshore wind power generation facility by power lines running under the seabed. The floating nuclear power generation system according to claim 2.

4. The system is further equipped with an emergency generator capable of supplying power to the aforementioned emergency system in the event of an emergency. The aforementioned emergency system is, Under normal circumstances, the power from the regular power generation equipment can be supplied to the regular power system via the emergency power system. In an emergency, by being disconnected from the normal power system, the power from the emergency generator and the normal power generation equipment is supplied only to the designated equipment. A floating nuclear power generation system according to claim 1.

Images