JP3982419B2 - Reactor safety equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to reactor safety equipment, and more particularly to a technique useful for water injection into a reactor pressure vessel and residual heat removal during reactor isolation.
[0002]
[Prior art]
Conventional boiling water reactor safety systems are emergency cooling systems (RCIC), residual heat removal systems (LPFL / RHR), and emergency power that generates and supplies power necessary for both systems. Emergency that generates and supplies power necessary for operation to Category I equipped with a diesel generator (emergency DG), high pressure core water injection system (HPCF), residual heat removal system (LPFL / RHR) Division II equipped with a diesel generator (emergency DG), and high pressure core injection system (HPCF), residual heat removal system (LPFL / RHR), emergency diesel generator (emergency DG) with the same configuration as Division II It consists of Category III with It should be noted that the reactor isolation cooling system (RCIC) can be started only with a DC power supply when all AC power is lost. The main steam relief safety valve is provided with an automatic pressure reducing device (ADS). Furthermore, as a related safety system, one containment vessel venting facility is installed when the reactor containment vessel becomes high pressure. Such a system in each section is a safety system using a so-called dynamic device that drives a pump in the system and exhibits a water injection function and a heat removal function. Conversely, a system that removes heat and water without using a pump is said to be a safety system using static equipment.
[0003]
In addition, a safety system using a static device is added (for example, refer to Patent Document 1) or a division of each category in order to improve the reliability of safety due to fear of start failure of a safety dynamic device. On the other hand, an example in which one of a plurality of safety systems using dynamic devices in a category is replaced with a safety system using static devices (for example, see Patent Document 2) is known.
[0004]
[Patent Document 1]
JP-A-7-253492
[Patent Document 2]
JP-A-8-313686
[0005]
[Problems to be solved by the invention]
In the conventional example, since the residual heat removal system (low pressure system) (LPFL / RHR) is arranged in three sections, this residual heat removal system heat exchanger is cooled and cooled with seawater as the final heat sink. Auxiliary equipment cooling system is required, and because of the large number of pumps and the like, the amount of equipment and the installation space for pumps and the like are increased, resulting in an increase in construction costs and maintenance costs.
[0006]
Further, even in a safety system using a conventional static device, no countermeasure has been taken to deal with a common cause failure for a DC power supply facility used as a power source for a motor-operated valve in the safety system.
[0007]
Furthermore, in the conventional example, the start-up of the reactor safety system is basically a manual start-up of the operator, but in order to further improve the reliability, a backup by an automatic start-up signal for the reactor heat removal system is required. However, there is a problem that the necessity is not satisfied.
[0008]
The main object of the present invention is to reduce the quantity of reactor safety equipment, and another object is to eliminate common cause failures in reactor safety equipment, and still another object is to ensure reactor safety. It is to provide a highly reliable boiling water reactor safety facility by automatically starting the facility.
[0009]
[Means for Solving the Problems]
Means for achieving the main object of the present invention includes a reactor containment vessel, a reactor pressure vessel stored in the reactor containment vessel, a main steam pipe connected to the reactor pressure vessel, A water supply pipe connected to the reactor pressure vessel, and a plurality of water injection systems for injecting water into the reactor pressure vessel, and a plurality of water injection systems for injecting water into the reactor pressure vessel A system that removes heat from the pressure vessel, a plurality of power supply facilities that are separated and independent for each section, and that supplies power to the equipment in the water injection system, and a condenser from the main steam pipe through the first pipe In the condenser system for condensing the vapor received in the condenser and returning the condensed water to the water supply pipe through the second pipe, and at least one of the first pipe and the second pipe, Equipped with multiple valves in parallel, The flow in the pipe is controlled to be intermittent. plural A first electric valve, each Supply power to the first motorized valve The different sections It is the safety equipment of a certain reactor as power supply equipment, Since the plurality of first motor-operated valves receives power from one of the power supply facilities in each section, the possibility that one valve operates reliably is increased. Since there is little possibility of loss of function of the isolation capacitor system, it is possible to reduce the number of dynamic devices and capacity of the water injection system.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Examples of the present invention will be described below. A nuclear power plant employing a boiling water reactor is provided with a reactor containment vessel 1 shown in FIG. The nuclear reactor containment vessel 1 contains the reactor pressure vessel 2 and the pressure suppression chamber in an airtight manner. The pressure suppression chamber includes a suppression pool 4 in which water is stored as pool water, and a wet well 58 space above the surface of the pool water. The space outside the pressure suppression chamber in the reactor containment vessel 1 is used as a device placement space or the like as a dry well 57. The dry well 57 and the surface of the suppression pool 4 communicate with each other through a vent passage 27 and a horizontal vent pipe 28.
[0011]
The reactor pressure vessel 2 airtightly stores a core 3 loaded with nuclear fuel therein. The core 3 is cooled by circulating the cooling water in the reactor pressure vessel 2 to the core 3 by an internal pump (not shown). In return, the cooling water that has passed through the core 3 is heated by the core 3. The Due to the heating, high-temperature and high-pressure steam is generated in the reactor pressure vessel 2.
[0012]
The steam generated in the reactor pressure vessel 2 passes through a main steam pipe 25 connected to the reactor pressure vessel 2, and receives steam that is present outside the reactor containment vessel 1, for example, a generator. Supplied to the driving steam turbine. The steam is consumed by a steam turbine or the like and then returned to water by a condenser (not shown). The water is used as cooling water in the reactor pressure vessel 2 through a water supply pipe 26 connected to the reactor pressure vessel 2. Returned to The water returned in this way is reused as cooling water circulating in the reactor pressure vessel 2 to the core 3.
[0013]
Since the main steam pipe 25 and the water supply pipe 26 extend to the steam utilization destination outside the reactor containment vessel 1, in order to prevent the expansion of radioactive contamination at the time of the accident, the main steam pipe 25 has a plant abnormality. Isolation valves 25 a and 25 b that are closed in the event of a transient event that is an event are provided inside and outside the reactor pressure vessel 2. Similarly, the water supply pipe 26 is provided with check valves 26 a and 26 b on the inside and outside of the reactor pressure vessel 2 for stopping the flow from the inside of the reactor containment vessel 1 toward the outside.
[0014]
The reactor safety equipment, that is, the reactor safety system, consists of the following systems, devices and equipment. The reactor safety system consists of two residual heat removal systems (LPFL / RHR), a high pressure core water injection system (HPCF), a reactor isolation cooling system (RCIC), an automatic decompressor (ADS), and a containment vessel vent facility. And a static containment vessel cooling system and an isolation capacitor system.
[0015]
Two residual heat removal systems (LPFL / RHR) are provided in the pipes 20a and 20b for communicating the pool water in the suppression pool 4 and the reactor pressure vessel 2, and the pipes 20a and 20b. Electric pumps 18a, 18b for driving the water in 20b toward the reactor pressure vessel 2, and heat exchangers 19a, 19b provided in the pipes 20a, 20b for cooling the water flowing in the pipes 20a, 20b, The motorized valves 21a and 21j provided in the pipes 20a and 20b so as to interrupt the flow in the pipes 20a and 20b outside the reactor containment vessel 1, and the pipes 20a and 20b inside the reactor containment vessel 1 There are provided check valves 21b and 21f provided on the pipes 20a and 20b so as to stop the flow in the outer direction of the reactor containment vessel 1 inside. The heat exchangers 19a and 19b are equipped with an auxiliary cooling system for passing seawater through the heat exchangers 19a and 19b as a fluid for cooling the heat exchangers 19a and 19b. An electric pump and an electric valve (not shown) driven by the same power supply equipment as the power supply equipment of the removal system (LPFL / RHR) are provided.
[0016]
The electric valves 21a and 21j and the electric pumps 18a and 18b of the residual heat removal system (LPFL / RHR) are controlled by two control circuits 29a and 29b. The control circuits 29a and 29b are equipped with one circuit for each residual heat removal system (LPFL / RHR), a total of two circuits.
[0017]
A plurality of branch pipes 201a, 202a, 203a, 201b, 202b, 203b are branched from such residual heat removal system (LPFL / RHR) pipes 20a, 20b, and each branch pipe 201a, 202a, 203a, 201b, 202b, Motorized valves 21d, 21c, 21e, 21h, which are arranged outside the reactor containment vessel 1 in the dry well 57 and the wet well 58 in the reactor containment vessel 1 and into the pool water of the suppression pool 4 It is extended via 21i and 21g. Branch pipes 201 a, 202 a, 201 b, 202 b extending into the dry well 57 and the wet well 58 are connected to spray headers 30, 31 arranged in the dry well 57 and the wet well 58.
[0018]
The residual heat removal system (LPFL / RHR) has a plurality of operation modes. The operation modes include a containment vessel spray mode, a suppression pool spray mode, a suppression pool cooling mode, and a low pressure water injection mode.
[0019]
The low-pressure water injection mode of the residual heat removal system (LPFL / RHR) is operated by starting the electric pumps 18a and 18b and opening the electric valves 21a and 21j when the reactor pressure vessel 2 is in a low pressure state. In the operation of the residual heat removal mode, the electric pumps 18a and 18b suck the pool water of the suppression pool 4 and inject it into the reactor pressure vessel 2 through the pipes 20a and 20b and the heat exchangers 19a and 19b. it can.
[0020]
In the residual heat removal system (LPFL / RHR) containment vessel spray mode, the electric pumps 18a and 18b are activated in a state where seawater is passed through the heat exchangers 19a and 19b in the auxiliary cooling system and cooled, It operates by opening the motorized valves 21b and 21h. In the operation of the storage container spray mode, the electric pumps 18a and 18b suck the pool water of the suppression pool 4 and supply water to the spray header 30 through the branch pipes 201a and 201b and the heat exchangers 19a and 19b. Pool water is sprinkled from 30 into the dry well 57 in the reactor containment vessel 1. Since the pool water is cooled by the heat exchangers 19 a and 19 b before the water spraying, the function of cooling the inside of the dry well 57 is exhibited by the pool water being sprayed into the dry well 57.
[0021]
The suppression pool spray mode of the residual heat removal system (LPFL / RHR) starts the electric pumps 18a and 18b in a state where seawater is passed through the heat exchangers 19a and 19b in the auxiliary cooling system and is cooled, It operates by opening the motorized valves 21e and 21i. In the operation of the suppression pool spray mode, the electric pumps 18a and 18b suck the pool water of the suppression pool 4 and supply the spray header 31 with water through the branch pipes 202a and 202b and the heat exchangers 19a and 19b. By the water supply, pool water is sprinkled from the spray header 31 into the wet well 58 in the pressure suppression chamber. Since the pool water is cooled by the heat exchangers 19a and 19b before watering, the pool water is sprayed into the wet well 58 from the spray header 31 so that the function of cooling the inside of the wet well 58 is exhibited.
[0022]
The suppression pool cooling mode of the residual heat removal system (LPFL / RHR) starts the electric pumps 18a and 18b in a state where seawater is passed through the heat exchangers 19a and 19b in the auxiliary cooling system and is cooled, Operation is performed by opening the motorized valves 21c and 21g. In the operation of the suppression pool cooling mode, the electric pumps 18a and 18b suck the pool water of the suppression pool 4 and send it to the heat exchangers 19a and 19b, where the pool water is cooled by the heat exchangers 19a and 19b. The circulation of the cooled pool water is repeated such that it is returned to the suppression pool 4 through the branch pipes 203a and 203b. Therefore, in the operation state of the suppression pool cooling mode, the function that the pool water in the suppression pool 4 is maintained in the cooled state is exhibited.
[0023]
The high pressure core water injection system (HPCF) includes a pipe 23 communicating the pool water in the suppression pool 4 and the reactor pressure vessel 2, and the water in the pipe 23 is provided to the reactor pressure vessel 2. An electric pump 22 that is driven toward, an electric valve 24 a provided in the pipe 23 so as to interrupt the flow in the pipe 23 outside the reactor containment vessel 1, and the pipe 23 inside the reactor containment vessel 1. And a check valve 24b provided in the pipe 23 so as to stop the outward flow of the reactor containment vessel 1 therein. The high-pressure core water injection system (HPCF) electric pump 22 and the electric valve 24 a are configured to be controlled by a control circuit 32.
[0024]
The high pressure core water injection system (HPCF) has a function of injecting pool water in the suppression pool 4 into the reactor pressure vessel 2 through the pipe 23 by the electric pump 22 by starting the electric pump 22 and opening the electric valve 24a. Can be demonstrated.
[0025]
The reactor isolation cooling system (RCIC) includes a pipe 16 that communicates between the pool water in the suppression pool 4 and the middle of the water supply pipe 26, and the water in the pipe 16 is provided in the pipe 16. , The steam turbine 33 that drives the pump 14, the main steam pipe 25 portion closer to the reactor pressure vessel 2 than the isolation valves 25 a, 25 b, and the driving steam receiving port of the steam turbine 33 Piping with continuous connection 35 And its piping 35 The piping so as to interrupt the flow inside 35 Motorized valve 15a provided in Isolation valves 15c and 15d , Piping communicating between the steam exhaust port of the steam turbine 33 and the pool water of the suppression pool 4 34 And its piping 34 The piping so as to interrupt the flow inside 34 Provided in Power And a valve 15b. Reactor isolation cooling system (RCIC) motorized valve 15a , 15b Is configured to be controlled by the control circuits 36a and 36b. Two control circuits 36a and 36b are prepared.
[0026]
The reactor isolation cooling system (RCIC) pipes the steam in the reactor pressure vessel 2 from the main steam pipe 25 by opening the motor-operated valves 15a and 15b in the state where the isolation valves 15c and 15d are opened. The steam turbine 33 is supplied to the steam turbine 33, and the steam turbine 33 is driven by the steam. When steam is supplied to the steam turbine 33 in this way, the turbine of the steam turbine 33 is rotationally driven by the steam. When the steam turbine 33 is driven, the pump 14 is driven by the steam turbine 33. When the pump 14 is driven, the pump 14 injects pool water in the suppression pool 4 into the water supply pipe 26 through the pipe 16, and the pool water injected into the water supply pipe 26 passes through the water supply pipe 26 to the reactor pressure. Water is poured into the container 2. In this way, the reactor isolation cooling system (RCIC) supplies from the reactor pressure vessel 2 side high pressure steam that can drive the pump with a predetermined driving force sufficient to inject water into the reactor pressure vessel 2. During this period, the function of pouring water into the reactor pressure vessel 2 can be exhibited. Note that the steam used in the steam turbine 33 is returned to the suppression pool 4 through the pipe 34.
[0027]
The automatic decompression device (ADS) shows a plurality of main steam relief safety valves 17 (only one valve is shown in FIG. 1) provided in the main steam piping 25 portion closer to the reactor pressure vessel 2 than the isolation valves 25a and 25b. ) And a pipe 17a that communicates the steam exhaust port of the main steam relief safety valve 17 and the pool water in the suppression pool 4. The main steam relief safety valve 17 is preset in operating pressure so that the main steam relief safety valve 17 is opened. When the pressure in the main steam pipe 25 rises above the set operating pressure, the main steam relief valve 17 is opened, and the steam in the main steam pipe 25 is opened together with the pressure in the suppression pool 4 via the pipe 17a. It has a relief valve function that allows it to escape into the pool water. The main steam relief safety valve 17 also has a safety valve function as a spring-type safety valve. The steam from the main steam relief safety valve 17 is condensed in the suppression pool 4 to suppress the pressure increase in the pressure suppression chamber as much as possible. The automatic pressure reducing device (ADS) reduces the pressure in the reactor pressure vessel 2 with respect to the plurality of main steam relief safety valves 17 until the low pressure water injection mode of the residual heat removal system (LPFL / RHR) can be activated. Demonstrate the function. The control circuits 66a and 66b for controlling the automatic pressure reducing device (ADS) have a control circuit for forcibly opening the main steam relief safety valve, and two circuits are provided.
[0028]
The isolation condenser system is provided in parallel with a pipe 9 that communicates the main steam pipe 25 portion closer to the reactor pressure vessel 2 than the isolation valves 25a and 25b and the inlet of the condenser 6, and in the middle of the pipe 9. The three motor-operated valves 7a, 7b, 7c, the outlet for discharging the condensed water in the condenser 6 and the water supply pipe 26 portion on the reactor pressure vessel 2 side than the check valves 26a, 26b are communicated with each other. The condenser 63 at a position higher than the outlet 63 for discharging the condensed water in the condenser 6, the three electric valves 8 a, 8 b, 8 c provided in parallel in the middle of the pipe 63, and the condenser 63. An outlet for exhausting the gas, a pipe 62 communicating the pool water in the suppression pool 4, three motor-operated valves 7 d, 7 e, 7 f provided in parallel in the middle of the pipe 62, and the outside of the reactor containment vessel 1 External pool 5 in which condenser 6 is submerged and stored It is equipped with a.
[0029]
The isolation condenser motorized valves 7a, 7b, 7c, 7d, 7e, 7f, 8a, 8b, and 8c are controlled by the reactor heat removal system control circuits 65a, 65b, and 65c. The reactor heat removal system control circuits 65a, 65b, and 65c are equipped with three circuits. Of each reactor heat removal system control circuit, the control circuit 65a controls the motorized valves 7a, 7d, 8a, the control circuit 65b controls the motorized valves 7b, 7e, 8b, and the control circuit 65c is controlled by the motorized valves 7c, 7f, 8c is controlled.
[0030]
The isolation capacitor system includes at least one valve of the three-valve motorized valves 7a, 7b, and 7c, at least one valve of the three-valve motorized valves 7d, 7e, and 7f and the motorized valve 8a, 8b of the three valves. , 8c and at least one valve is opened. Thus, when at least one valve is opened for each group, the steam in the reactor pressure vessel 2 enters the condenser 6 through the main steam pipe 25 and the pipe 9. Since the condenser 6 is submerged and cooled in the pool water of the external pool 5, the vapor that has entered the condenser 6 is cooled and condensed in the condenser 6. The steam condensed in the condenser 6 returns to the water, enters the water supply pipe 26 through the pipe 63, and is further poured into the reactor pressure vessel 2 from the water supply pipe 26 to be returned. Thus, the isolation capacitor system exhibits the function of condensing the steam generated in the reactor pressure vessel 2 and removing the decay heat of the core 3.
[0031]
In addition, before the condensation of the vapor by the condenser 6 is started, the condenser 6 is filled with gas. The gas is pushed by the vapor that has entered the condenser 6 and is exhausted from the condenser 6 into the pool water in the suppression pool 4 through the pipe 62.
[0032]
The static containment vessel cooling system includes a pipe 67 that connects the inside of the dry well 57 of the reactor containment vessel 1 and the inlet of the heat exchanger 10, an outlet that discharges the fluid after heat exchange of the heat exchanger 10, and a suppression. A pipe 11 that communicates the pool water in the pool 4 and an external pool 5 that stores the heat exchanger 10 by immersing it outside the reactor containment vessel 1 are provided. Each external pool 5 is a series and is sealed.
[0033]
In the static containment vessel cooling system, for example, when steam generated in the reactor pressure vessel 2 leaks into the dry well 57 and the pressure in the dry well 57 becomes relatively higher than the pressure in the pressure suppression chamber, The vapor in the dry well 57 enters the heat exchanger 10 through the pipe 67, where it condenses into water. The water is put into the pool water of the suppression pool 4 through the pipe 11. Thus, the static containment vessel cooling system exhibits the function of condensing the vapor in the reactor containment vessel 1 to cool the inside of the reactor containment vessel 1 and lowering the pressure in the reactor pressure vessel 2. .
[0034]
Two systems for the containment venting system are adopted. One of them can intermittently connect the pipe 13 for guiding gas from the wet well 58 and the dry well 57 in the reactor containment vessel 1 to the exhaust pipe 56 installed outside the reactor containment vessel 1 and the flow in the pipe 13. Thus, each motor-operated valve 12a, 12b, 12c provided in the middle of the pipe 13 is provided. The motor-operated valves 12a, 12b, and 12c in this system are controlled by the reactor heat removal system control circuits 65a, 65b, and 65c.
[0035]
The other containment vessel vent system is a pipe 59 that allows the wet well 58 and dry well 57 in the reactor containment vessel 1 to communicate with the pool water of the external pool 5, and the pipe 59 so that the flow in the pipe 59 can be interrupted. 59, each motor-operated valve 12d, 12e, 12f provided in the middle of 59, and a pipe 60 for guiding gas from the gas phase space above the pool water surface of the external pool 5 to the exhaust pipe 56. The motor-operated valves 12d, 12e, and 12f in this system are controlled by the reactor heat removal system control circuits 65a, 65b, and 65c.
[0036]
In the containment vessel vent system, one system is operated by opening each motor-operated valve 12a, 12b, 12c, and the other system is operated by opening each motor-operated valve 12d, 12e, 12f. Since the containment vessel venting equipment is operated in a state where the pressure in the reactor containment vessel 1 is higher than the external pressure for the purpose of reducing the pressure in the reactor containment vessel, each motor operated valve 12a, 12b, When 12c is opened, the pressure inside the reactor containment vessel 1 and the atmosphere inside the reactor containment vessel 1 are sent to the exhaust pipe 56 through the pipe 13 by the differential pressure between the pressure inside the reactor containment vessel and the outside world. To be missed. Further, by opening the motor-operated valves 12d, 12e, and 12f, the pressure and atmosphere in the reactor containment vessel 1 are discharged into the pool water of the external pool 5 through the pipe 59, and are included in the atmosphere here. The steam is condensed in the pool water, the water-soluble radionuclide contained in the atmosphere remains in the pool water, and the atmosphere and pressure from which the water-soluble radionuclide has been removed are sent to the exhaust pipe 56 through the pipe 60, The exhaust tube 56 escapes to the outside world. Thereby, the containment vessel vent facility exhibits a function of suppressing an abnormal rise in pressure and temperature in the reactor containment vessel 1.
[0037]
As described above, the safety system of the boiling water reactor according to the embodiment of the present invention includes the residual heat removal system (LPFL / RHR), the reactor isolation cooling system (RCIC), the high-pressure core water injection system (HPCF), It consists of an automatic decompression device (ADS), a containment vessel vent facility, an isolation condenser system (IC), and a static containment vessel cooling system.
[0038]
FIG. 2 shows the system division of the safety system according to this embodiment, and FIG. 4 shows the system division of the power supply system of the safety system according to this embodiment. All sections are assigned a common number as the section number.
[0039]
Section I shown in FIG. 2 is the residual heat removal system (LPFL / RHR) and emergency diesel generator 37 for supplying electricity to the equipment belonging to the section, and section II is the residual heat removal system (LPFL / RHR) and the section The emergency diesel generator 38 for supplying electricity to the equipment belonging to No. 3 and section III are provided with a high pressure core water injection system (HPCF) and an emergency diesel generator 39 for supplying electricity to the equipment belonging to that section.
[0040]
Thus, the safety system includes an emergency diesel generator as an emergency power supply facility for each of the aforementioned sections. In addition, electricity is supplied independently for each section from an external power supply outside the nuclear plant, that is, a power supply facility outside the nuclear plant via a transmission line.
[0041]
When the power supply system for each section is shown, an independent power supply system is established for each section as shown in FIG. That is, in the power supply system of section I, the two power supply facilities of the external power supply and the emergency diesel generator 37 can supply AC 6.9 kv AC power to the high-voltage AC electric wire 68a. If the supply of power from the external power supply does not stop, AC power is received from the external power supply to the high-voltage AC wire 68a, and when the supply of power from the external power supply stops, the emergency diesel generator 37 is activated. AC power is supplied to the high-voltage AC wire 68a. The high-voltage AC electric wire 68a is connected to the electric pump 18a of the residual heat removal system (LPFL / RHR) of section I through a circuit breaker, and the electric pump 18a is activated by the electric pump 18a from the high-voltage AC electric wire 68a. Necessary power can be obtained.
[0042]
Transformer from high voltage AC wire 68a 69 AC480v AC power is supplied to the low-voltage AC wire 70a via a. The low-voltage AC electric wire 70a is connected to a motor I 21c of the residual heat removal system (LPFL / RHR) of section I and motor valves 12a, 12b, 12c of the containment vessel venting equipment through a circuit breaker. The electric valves 21c, 12a, 12b, and 12c can obtain electric power required for starting the electric valves 21c, 12a, 12b, and 12c from the low-voltage AC electric wire 70a.
[0043]
A charger is connected to the low-voltage AC wire 70a through a circuit breaker. The AC power of the low-voltage AC electric wire 70a is converted into DC 125v DC power by the charger and flows to the DC electric wire 71a. A storage battery 40 is connected to the DC electric wire 71a through a circuit breaker. The storage battery 40 can store electric power from the DC electric wire 71a through the circuit breaker, or can discharge DC electric power to the DC electric wire 71a when the AC power supply is lost.
[0044]
Further, the DC electric wire 71a includes the motor isolation valves 15a, 15b and the isolation valves 15c, 15d, the control circuits 29a, 36a, 65a, 65b and the isolation condenser motors 7a, 7d, 8a. Are connected individually via circuit breakers, and the direct-current power necessary for the activation of these motor-operated valves and isolation valves, or the operation of their control circuits, Each of the control circuits can receive power.
[0045]
The residual heat removal system (LPFL / RHR) control circuit 29a includes a circuit breaker connected to the electric pumps 18a and the motor operated valves 21a, 21c, 21d, 21e adapted to the operation mode of the residual heat removal system (LPFL / RHR). By switching from the non-energized state to the energized state, the motor-operated valve 21c closed in the non-energized state can be opened, and the electric pump 18a stopped in the non-energized state can be controlled.
[0046]
The control circuit 36a of the reactor isolation cooling system (RCIC) switches the circuit breaker connected to the motor operated valves 15a and 15b from the non-energized state to the energized state with the isolation valves 15c and 15d open. It is possible to perform control to open the motor-operated valve that has been closed in a non-energized state.
[0047]
The control circuit 66a of the automatic pressure reducing device (ADS) can control the main steam relief safety valve 17 by controlling the pressure circuit of the cylinder device that forcibly opens the main steam relief safety valve 17. Another state in which the main steam relief safety valve 17 is forcibly opened is when the main steam relief safety valve 17 receives a pressure higher than the set pressure from the main steam pipe.
[0048]
The reactor heat removal system control circuit 65a operates the operation of the control circuit 29a of the residual heat removal system (LPFL / RHR), the motor operated valves 7a, 7d, 8a of the isolation capacitor system (IC), and the motor operated valve 12a of the containment vent system. , 12b, and 12c are provided. When the reactor heat removal system control circuit 65a generates the start signal, the reactor heat removal system control circuit 65a switches the circuit breaker of the control circuit 29a of the residual heat removal system (LPFL / RHR) from the non-energized state to the energized state. The control circuit 29a of the residual heat removal system (LPFL / RHR) is activated, and the control circuit 29a of the residual heat removal system (LPFL / RHR) is activated to activate the electric pump 18a and open the electric valve 21c. I do. When the reactor heat removal system control circuit 65a generates a start signal, the reactor heat removal system control circuit 65a includes a circuit breaker connected to the motor-operated valves 7a, 7d, and 8a of the isolation capacitor system (IC). Control is performed to switch the circuit breaker connected to the motor-operated valves 12a, 12b, 12c of the containment vessel vent facility from the non-energized state to the energized state. By this control, the motor operated valves 7a, 7d, 8a of the isolation capacitor system (IC) that has received DC power and the motor operated valves 12a, 12b, 12c of the containment vent system are changed from the closed state to the opened state.
[0049]
FIG. 5 shows the circuit configuration of the reactor heat removal system control circuit 65a as an equivalent logic circuit. That is, the nuclear power plant measures the water level and pressure of the cooling water in the reactor pressure vessel 2, the water temperature of the pool water in the suppression pool 4, the pressure, temperature and radiation dose in the reactor containment vessel 1 (see FIG. (Not shown) to monitor the status of the nuclear power plant. Reactor water level low signal (indicated in the figure as low reactor water level) 50 generated when the water level in the reactor pressure vessel 2 is lower than the preset water level from the measurement system, and the reactor pressure from the measurement system The containment vessel pressure high signal (indicated as PCV pressure high in the figure) 51 generated when the pressure in the vessel 2 is higher than a preset pressure, and the water temperature of the pool water in the suppression pool 4 from the measurement system Suppression pool water temperature high signal (shown as S / P water temperature high in the figure) 52 that is issued when the temperature is higher than the set temperature, and a manual activation signal that is generated by turning on a manual switch provided in the control room of the nuclear power plant The reactor heat removal system control circuit 65a can receive 53 (manual activation and display in the figure).
[0050]
In this case, the set pressure of the containment vessel pressure high signal is the highest set pressure of the containment vessel 1 in which the nuclear power plant is operated, and the set water temperature of the suppression pool 4 is high when the nuclear power plant is operated. The set temperature of the pool water of the suppression pool 4 is the highest, and the set water level of the low water level in the reactor pressure vessel 2 is the lowest water level at which the core 3 in the reactor pressure vessel 2 can be cooled to a safe state. Has been.
[0051]
When the reactor heat removal system control circuit 65a generates the activation signal, the manual activation signal 53 is input to the reactor heat removal system control circuit 65a, or the measurement system sends the activation signal to the reactor heat removal system control circuit 65a. This is the case when the signal has the following conditions. The conditions are when the reactor water level low signal 50 is not generated, the containment vessel pressure high signal 51 is generated, and the suppression pool water temperature high signal 52 is generated.
[0052]
Under such conditions, the reactor heat removal system control circuit 65a generates a start signal, and the suppression pool cooling of the isolation condenser system (IC), the containment vessel vent facility, and the residual heat removal system (LPFL / RHR) is performed. A start signal for starting each motor-operated valve or motor-pump related to the mode is generated.
[0053]
By providing such a reactor heat removal system control circuit 65a, a start signal is automatically generated and the reactor water level is maintained without recognizing the need for manual start-up. Thus, the isolation capacitor system (IC), the containment vessel vent facility, and the residual heat removal system (LPFL / RHR) can be reliably operated.
[0054]
Further, as a logic circuit equivalent to the circuit configuration of the reactor heat removal system control circuit 65a, the logic circuit configuration as shown in FIG. 6 achieves the same function as the logic circuit configuration of FIG. Further, as shown in FIGS. 7 and 8, it is possible to provide a logic circuit configuration that improves reliability by providing a time delay signal.
[0055]
As shown in FIG. 4, the power supply system of section II is different in that there is no DC power supply circuit from the power supply system of section I to the motor-operated valve of the reactor isolation cooling system, and the others are very similar. That is, the power supply system of Category II is as follows. Two power supply facilities, an external power supply and an emergency diesel generator 38, can supply AC 6.9 kv AC power to the high-voltage AC electric wire 68b. If the supply of power from the external power supply does not stop, AC power is received from the external power supply to the high-voltage AC wire 68b, and when the supply of power from the external power supply stops, the emergency diesel generator 38 is activated. AC power is supplied to the high-voltage AC wire 68b. The electric pump 18b of the residual heat removal system (LPFL / RHR) of section II is connected to the high-voltage AC electric wire 68b through a circuit breaker, and the electric pump 18b is used for starting the electric pump 18b from the high-voltage AC electric wire 68b. Necessary power can be obtained.
[0056]
AC 480v AC power is supplied from the high voltage AC wire 68b to the low voltage AC wire 70b via the transformer 69b. The low-voltage AC electric wire 70b is connected to a motor II 21g of the residual heat removal system (LPFL / RHR) of section II and motor-operated valves 12d, 12e, 12f of the containment vessel vent equipment through a circuit breaker. The electric valves 21g, 12d, 12e, and 12f can obtain electric power necessary for starting the electric valves 21g, 12d, 12e, and 12f from the low-voltage AC electric wire 70b.
[0057]
A charger is connected to the low-voltage AC electric wire 70b through a circuit breaker. The AC power of the low-voltage AC electric wire 70b is converted into DC 125v DC power by the charger and flows to the DC electric wire 71b. A storage battery 41 is connected to the DC electric wire 71b through a circuit breaker. The storage battery 41 can store electric power from the DC electric wire 71b through the circuit breaker, or can discharge DC electric power to the DC electric wire 71b when the AC power source is lost.
[0058]
Further, the control circuit 29b, 36b, 65b, 66b and the isolation capacitor type motor operated valves 7b, 7e, 8b are individually connected to the DC electric wire 71b via a circuit breaker, and the motor operated valves 7b, 7e, The DC power necessary for starting 8b or for operating the control circuits 29b, 36b, 65b, 66b is supplied to the electric valves 7b, 7e, 8b and the control circuits 29b, 36b, 65b, 66b. Can receive power.
[0059]
The residual heat removal system (LPFL / RHR) control circuit 29b includes a circuit breaker connected to the electric valves 21g, 21h, 21i, and 21j adapted to the operation mode of the electric pump 18b and the residual heat removal system (LPFL / RHR). By controlling to switch from the non-energized state to the energized state, the motor-operated valve 21g that was closed in the non-energized state is opened in the energized state, and the electric pump 18b that has been stopped in the non-energized state is controlled to start in the energized state. it can.
[0060]
The control circuit 36b of the reactor isolation cooling system (RCIC) controls the circuit breaker connected to the motor operated valves 15a and 15b from the non-energized state to the energized state when the isolation valves 15c and 15d are opened. Thus, it is possible to perform control to open the motor-operated valves 15a and 15b that are closed in the non-energized state in the energized state.
[0061]
The control circuit 66b of the automatic pressure reducing device (ADS) can control the main steam relief safety valve 17 by controlling the pressure circuit of the cylinder device that forcibly opens the main steam relief safety valve 17. Another state in which the main steam relief valve 17 is open is when the main steam relief valve 17 receives a pressure higher than the set pressure from the main steam pipe.
[0062]
The reactor heat removal system control circuit 65b operates the operation of the control circuit 29b of the residual heat removal system (LPFL / RHR), the motor operated valves 7b, 7e, 8b of the isolation capacitor system (IC), and the motor operated valve 12d of the containment vent system. , 12e, and 12f are provided. When the reactor heat removal system control circuit 65b generates the start signal, the reactor heat removal system control circuit 65b switches the circuit breaker of the control circuit 29b of the residual heat removal system (LPFL / RHR) from the non-energized state to the energized state. The control circuit 29b of the residual heat removal system (LPFL / RHR) is activated, and the control circuit 29b of the residual heat removal system (LPFL / RHR) is activated to activate the electric pump 18b and open the electric valve 21g. I do. When the reactor heat removal system control circuit 65b generates the start signal, the reactor heat removal system control circuit 65b is connected to the motor operated valves 7b, 7e, 8b of the isolation capacitor system (IC) and the containment vessel. Control is performed to switch the circuit breaker connected to the motor operated valves 12d, 12e, and 12f of the vent facility from the non-energized state to the energized state. By this control, the motor operated valves 7b, 7e, 8b of the isolation capacitor system (IC) that has received DC power and the motor operated valves 12d, 12e, 12f of the containment vent system are changed from the closed state to the opened state.
[0063]
If the circuit configuration of the reactor heat removal system control circuit 65b of section II is shown by an equivalent logic circuit, it is the same as that of section I, and the condition for the reactor heat removal system control circuit 65b to generate the start signal is that of section I As in the case, there is a case where there is a manual activation signal, or a case where the reactor water level low signal 50 is not generated, the containment vessel pressure high signal 51 is generated, and the suppression pool water temperature high signal 52 is generated.
[0064]
Under such conditions, the reactor heat removal system control circuit 65b generates a start signal, and the motors 7b, 7e, 8b of the isolation capacitor system (IC) and the motorized valves 12d, 12e, 12f and the electric pump 18b and the electric valve 21g of the residual heat removal system (LPFL / RHR) of Section II are opened or activated.
[0065]
By providing such a reactor heat removal system control circuit 65b, a start signal is finally generated and the reactor water level is maintained without recognizing a situation where it is necessary to start manually in Section II. Under certain circumstances, the isolation capacitor system (IC), the containment vent system, and the residual heat removal system (LPFL / RHR) of section II can be started.
[0066]
As shown in FIG. 4, the power supply system of Section III is configured such that the two power supply facilities of the external power supply and the emergency diesel generator 39 can supply AC 6.9 kv AC power to the high-voltage AC electric wire 68c. If power is supplied from the external power supply, AC power is received from the external power supply to the high-voltage AC power line 68c, and when the power supply from the external power supply is stopped, the emergency diesel generator 39 is activated and the high voltage is supplied. AC power is supplied to the AC wire 68c. The high-pressure AC electric wire 68c is connected to an electric pump 22 of a high-pressure core water injection system (HPFL) through a circuit breaker, and the electric pump 22 obtains electric power necessary for starting the electric pump 22 from the high-pressure AC electric wire 68c. be able to.
[0067]
AC 480v AC power is supplied from the high voltage AC wire 68c to the low voltage AC wire 70c via the transformer 69c. A high pressure core water injection system (HPFL) motor-operated valve 24a is connected to the low-voltage AC electric wire 70c via a circuit breaker, and the motor-operated valve 24a receives electric power necessary for starting the motor-operated valve 24a from the low-voltage AC electric wire 70c. Obtainable.
[0068]
A charger is connected to the low-voltage AC wire 70c through a circuit breaker. The AC power of the low-voltage AC wire 70c is converted into DC 125v DC power by the charger and then flows to the DC wire 71c. A storage battery 42 is connected to the DC electric wire 71c through a circuit breaker. The storage battery 42 can store electric power from the DC electric wire 71c through the circuit breaker, or can discharge DC electric power to the DC electric wire when the AC power source is lost.
[0069]
Further, the control circuit 32, 65c and the isolation condenser type motor operated valves 7c, 7f, 8c are individually connected to the DC electric wire 71c via a circuit breaker, and the motor operated valves 7c, 7f, 8c are activated. Therefore, the motor-operated valves 7c, 7f, 8c and the control circuits 32, 65c can receive DC power necessary for the operation of the control circuits 32, 65c.
[0070]
The control circuit 32 of the high-pressure core water injection system (HPFL) controls the motor-operated valve 24a closed in the non-energized state by controlling the circuit breaker connected to the motor-driven pump 22 and the motor-operated valve 24a from the non-energized state to the energized state. It is possible to perform control for starting the electric pump 22 that is open in the energized state and stopped in the non-energized state in the energized state.
[0071]
The reactor heat removal system control circuit 65c has a circuit configuration for starting the motors 7c, 7f, and 8c of the isolation capacitor system (IC). When the reactor heat removal system control circuit 65c generates a start signal, the reactor heat removal system control circuit 65c turns off the circuit breakers connected to the motor operated valves 7c, 7f, and 8c of the isolation capacitor system (IC). Control to switch from the current state to the energized state. By the control, the motor operated valves 7c, 7f, and 8c of the isolation capacitor system (IC) that receives DC power are changed from the closed state to the opened state.
[0072]
If the circuit configuration of the reactor heat removal system control circuit 65c of section III is shown by an equivalent logic circuit, it is the same as that of section I, and the condition for the reactor heat removal system control circuit 65c to generate the start signal is that of section I As in the case, there is a case where there is a manual activation signal, or a case where the reactor water level low signal 50 is not generated, the containment vessel pressure high signal 51 is generated, and the suppression pool water temperature high signal 52 is generated.
[0073]
Under such conditions, the reactor heat removal system control circuit 65c generates a start signal and operates the motors 7c, 7f, 8c of the isolation capacitor system (IC) to open.
[0074]
By providing such a reactor heat removal system control circuit 65c, a startup signal is finally generated and the water level of the reactor is maintained without recognizing the situation where manual startup is required even in Section III. It is possible to reliably start the isolation capacitor system (IC) in some situations.
[0075]
As described above, the isolation capacitor system (IC) can be operated by any electric power of any section, so if any one of the storage batteries 40, 41, 42 functions normally, it is generated in the reactor pressure vessel 2. The heat removal function is not lost.
[0076]
In the present embodiment, as shown in FIG. 1, the nuclear power plant is operated with the isolation valves 25a, 25b, 15c, and 15d shown in white and opened, and the valves shown in black are closed. . In such a normal state, the cooling water heated in the reactor core 3 in the reactor pressure vessel 2 is supplied as steam to the outside of the reactor containment vessel 1 through the main steam pipe 25 and is used from the supply destination after use. Steam becomes ascites and is returned to the reactor pressure vessel 2 via the water supply pipe 26. During such normal operation, the temperature and pressure in the reactor pressure vessel 2 and the reactor containment vessel 1 and the temperature of the pool water in the suppression pool 4 are kept in a state that is acceptable in normal operation.
[0077]
When the nuclear power plant is in any abnormal state, the isolation valves 25a and 25b are closed to stop the supply of steam to the supply destination in an abnormal state. By closing the isolation valves 25a and 25b, the steam pressure in the reactor pressure vessel 2 rises to a pressure higher than that permitted in normal operation, that is, a set pressure at which the main steam relief safety valve 17 opens, and finally the main steam relief safety valve 17 Opens. When the main steam relief safety valve 17 is opened, steam and pressure in the reactor pressure vessel 2 are exhausted into the pool water of the suppression pool 4 through the main steam relief safety valve 17 and the pipe 17a. The steam in the exhaust is condensed in the pool water of the suppression pool 4, and the non-condensed gas accumulates in the wet well 58 to increase the pressure in the pressure suppression chamber and the temperature of the pool water.
[0078]
The temperature of the pool water in the suppression pool 4 is safe because it decreases in the operation of the suppression pool cooling mode of the residual heat removal system (LPFL / RHR), but the residual heat removal system (LPFL / RHR) does not function and is suppressed. When the exhaust of the pool 4 into the pool water continues, the pressure in the pressure suppression chamber and the temperature of the atmosphere rise. Although not shown, the pressure in the pressure suppression chamber is checked. Through valve Then, the pressure and atmosphere in the pressure suppression chamber are transferred into the dry well 57 through the flow path that escapes into the dry well 57. Therefore, it is necessary to consider the countermeasures assuming that the reactor containment vessel 1 constituting the primary boundary such as the radioactivity and radiation of the nuclear power plant becomes dangerous beyond the design conditions. Assuming a cause that is considered to cause such danger, that is, an abnormal event of the nuclear power plant, it will be described below that the nuclear power plant according to the present embodiment is a safety facility in which such a cause hardly occurs.
[0079]
In the configuration of the present embodiment, as shown in FIG. 4, the AC power source is a power source, and the DC power source is required for control with two residual heat removal systems (LPFL / RHR) and one high pressure core cooling system. As a system that can be activated and controlled only by DC power, it has a reactor isolation cooling system (RCIC) and an isolation capacitor system (IC). Therefore, even if the external power supply is lost, even if all AC power is lost, even if the residual heat removal system (LPFL / RHR) 2 system and the high pressure core 3 cooling system 1 system are not activated by losing the AC power, the DC from the storage battery Reactor isolation cooling system (RCIC) and isolation capacitor system (IC) can be activated and controlled with only power supply to ensure highly reliable water injection and heat removal capabilities.
[0080]
Moreover, the only AC power source required for Category III is the high pressure core cooling system and the system (not shown) for cooling its auxiliary equipment, and the load on the emergency diesel generator 39 can be reduced compared to other categories. By adopting an emergency diesel generator 39 and a storage battery 42 of a different type with a smaller capacity than the other divisions in III, common cause failures among the divisions can be reduced. In this way, the occurrence probability of the loss of AC power or DC power at the same time in three sections due to the same type of emergency diesel generators 37 and 38 and emergency diesel generator 39 and storage batteries 40 and 41 and storage battery 42 is obtained. It is decreasing.
[0081]
In addition, as a plant abnormal event of a boiling water reactor, the loss of external power occurs, and the common cause failure of the storage batteries 40, 41 causes the emergency diesel generators of category I and II to receive power from the storage batteries 40, 41 at startup. Even if the heat removal by the residual heat removal system (LPFL / RHR) cannot be performed without starting, the motors 7c, 7f, 8c of the isolation capacitor system (IC) fed from the storage battery 42 of Section III are opened. Therefore, the heat removal by the isolation capacitor system is possible, and there is no concern that the heat removal function is lost at all.
[0082]
Further, when a turbine trip or loss of water supply occurs as a transient event that is an abnormal event of the nuclear power plant, the reactor pressure vessel 2 is in an initial stage immediately after the isolation valves 25a and 25b are closed and the reactor is isolated. In the state that one of the plurality of main steam relief safety valves 17 is not closed, that is, one valve is stuck open. is assumed.
[0083]
In that case, the steam in the reactor pressure vessel 2, that is, the reactor steam, is guided to the suppression pool 4 through the main steam relief safety valve 17 which remains open, so that the reactor pressure is reduced, and finally the steam using the reactor steam as a driving energy source. The turbine 33 cannot sufficiently drive the pump 14 of the reactor isolation cooling system (RCIC), the reactor isolation cooling system (RCIC) cannot be started, and the reactor pressure by the reactor isolation cooling system (RCIC) Water injection into the container 2 becomes impossible. Therefore, the cooling water (pool water) in the suppression pool 4 is injected into the reactor pressure vessel 2 by a high-pressure core water injection system (HPCF).
[0084]
In this case, water injection into the reactor pressure vessel 2 is successful in the high-pressure core water injection system (HPCF), but the decay heat of the core 3 has been transferred to the suppression pool 4, and the pool water in the suppression pool 4 is cooled. There is a need. However, if the two systems of the residual heat removal system (LPFL / RHR) that cools the pool water of the suppression pool 4 fail to start, the cooling function cannot be used, so the containment vessel vent facility installs the reactor containment vessel 1. The atmosphere and pressure in the reactor containment vessel 1 are released from the gas phase inside to the atmosphere via the exhaust tube 56 to dissipate decay heat.
[0085]
The containment vessel venting equipment drains the pipe 60 from the reactor containment vessel 1 to the exhaust pipe 56 through the pipe 13, the pipe 59 leading from the reactor containment vessel 1 into the external pool, and the gas phase part of the external pool 5. It was generated in the reactor pressure vessel 2 by the isolation capacitor system (IC), ensuring the multiplicity of releasing the atmosphere and pressure in the reactor containment vessel 1 to the atmosphere in two systems with the other system leading to the cylinder. The reliability of the exhaust heat function when heat removal is impossible is improved.
[0086]
In addition, the containment vessel venting system is designed to prevent the dry well of the reactor containment vessel 1 when the pressure in the reactor containment vessel 1 exceeds the design condition under the core damage accident condition due to the multiple failures of the safety system exceeding the design standard accident. When venting from the 57 part to the exhaust stack is required, the pressure and atmosphere in the reactor containment vessel 1 can be guided to the exhaust stack 56 through the water in the external pool 5. Water-soluble radionuclides out of the radionuclides leaking out into the wells or already existing in 57 parts of the dry well can be removed in the water of the external pool.
[0087]
Further, in this embodiment, when the pressure in the dry well 57 part of the reactor containment vessel 1 is higher than that of the wet well 58 part of the reactor containment vessel 1 under the accident condition, the heat exchanger 10 of the static containment vessel cooling system is used. It is possible to reduce the pressure and temperature in the reactor pressure vessel 2 by condensing the vapor in the 57 parts of the dry well or cooling the atmosphere.
[0088]
Next, as a result of measurement by the measurement system in the nuclear power plant, when the reactor water level low signal 50 is not generated, the containment vessel pressure high signal 51 is generated, and the suppression pool water temperature high signal 52 is generated, the reactor is removed. Since the heat system control circuits 65a, 65b, and 65c automatically generate the start signal 54, the motor valve for the isolation capacitor system (IC), the motor valve for the containment vent system, and the residual heat removal system (LPFL / RHR) ) The electric pump and the electric valve are automatically opened or started. The set pressure of the containment vessel pressure and the set temperature of the suppression pool water temperature are the highest of the set values of the boiling water reactor. Even without knowing the need to manually activate the vessel vent facility and the residual heat removal system (LPFL / RHR) suppression pool cooling mode, an activation signal 54 is eventually generated to maintain the reactor water level. In this situation, the suppression pool cooling mode of the isolation capacitor system (IC), the containment vessel venting facility, and the residual heat removal system (LPFL / RHR) can be reliably activated.
[0089]
Thus, the isolation condenser system (IC), the containment vessel vent equipment, the residual heat, and the activation signal 54 automatically generated by the signals of the reactor water level high, the containment vessel pressure high, and the suppression pool water temperature high. The activation of the suppression pool cooling mode of the removal system (LPFL / RHR) becomes more reliable, and the reliability of the reactor heat removal system composed of these is improved.
[0090]
Also, as shown in FIG. 3, the isolation capacitor system (IC) is omitted from the motor operated valves 7a, 7b, 7c, 7d, 7e, 7f and the piping 62 in FIG. The valves 7 and 64 may be provided, and the other configuration may be the same as in the case of FIG. In this case, normally, the isolation valves 7 and 64 are opened, the main steam pipe 25 and the condenser 6 are opened through the pipe 9, and the isolation condenser system (IC) is activated. The valves 8a, 8b and 8c are opened. In this way, since the heat and pressure of steam are constantly applied to the pipe 9, the condenser 6, and the motorized valves 8a, 8b, and 8c before starting the isolation capacitor system (IC), the isolation capacitor system ( When the IC) is activated, shocks such as thermal load and pressure fluctuation applied to the components of the isolation capacitor system (IC) can be reduced, and damage to the isolation capacitor system (IC) can be suppressed.
[0091]
Thus, according to the embodiment of the present invention, regarding the safety equipment of a nuclear power plant, when an event such as loss of an external power source occurs while reducing the amount of equipment, a common cause failure that is assumed to occur On the other hand, reliability can be improved. Also, by adopting the isolation capacitor system (IC), which is a static system of nuclear plant safety equipment, and the containment venting equipment, the heat removal system of the nuclear plant safety equipment is multiplexed and diverse. I tried to change. In addition, automatic startup of the heat removal system is possible, reducing the burden on the operator and improving the reliability of safety equipment.
[0092]
【The invention's effect】
As described above, according to the present invention, since the isolation capacitor system (IC), which is a static heat removal equipment, can be activated using any power supply equipment, dynamic heat removal is possible. It is no longer necessary to prepare a facility for removing residual heat in all sections, and the amount of safety equipment in the nuclear power plant can be reduced.
[Brief description of the drawings]
FIG. 1 is a system diagram of safety equipment of a nuclear power plant according to an embodiment of the present invention.
FIG. 2 is a division diagram of the system of the safety equipment of FIG.
FIG. 3 is a system diagram showing a modification of the isolation capacitor system (IC) of FIG. 1;
4 is a division diagram of a power supply system of the safety facility of FIG. 1. FIG.
FIG. 5 is a logic circuit diagram of a control circuit of the reactor heat removal system of the safety facility of FIG. 1;
6 is a logic circuit diagram according to a modification of the logic circuit of FIG.
7 is a logic circuit diagram according to another modification of the logic circuit of FIG.
FIG. 8 is a logic circuit diagram according to still another modification of the logic circuit of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reactor containment vessel, 2 ... Reactor pressure vessel, 3 ... Core, 4 ... Suppression pool, 5 ... External pool, 6 ... Condenser, 7a-7f, 8a-8c, 12a-12f, 15a, 15b, 21a -21j, 24a ... motorized valve, 9, 11, 13, 16, 20a, 20b, 23, 34, 35, 59, 60, 62, 63, 67 ... piping, 10, 19a, 19b ... heat exchanger, 14 ... Pump, 17 ... main steam relief safety valve, 18a, 18b, 22 ... electric pump, 25 ... main steam pipe, 26 ... water supply pipe, 37, 38, 39 ... emergency diesel generator, 40, 41, 42 ... storage battery, 50 ... reactor water level low signal, 51 ... containment pressure high signal, 52 ... suppression pool water temperature high signal, 53 ... manual start signal, 54 ... start signal, 56 ... exhaust pipe, 57 ... dry well, 58 ... wet , 65a, 65b, 65c ... reactor heat removal system control circuit.

Claims (6)

A containment vessel,
A reactor pressure vessel stored in the reactor containment vessel;
A main steam pipe connected to the reactor pressure vessel;
A water supply pipe connected to the reactor pressure vessel;
A plurality of water injection systems for injecting water into the reactor pressure vessel and a system for removing heat from the reactor pressure vessel in two sections among the plurality of sections;
A plurality of power supply facilities that are separated and independent for each of the sections and supply power to the devices in the water injection system,
An isolation condenser system for condensing steam received in the condenser from the main steam pipe via the first pipe in the condenser and returning the condensed water to the water supply pipe through a second pipe;
A plurality of first motor-operated valves that are equipped in parallel with a plurality of valves in at least one of the first pipe and the second pipe , and that control the flow in the pipe in an intermittent manner;
It said safety system for a reactor with as the power supply equipment of the segments different from each other to supply power to the first electric valve. Te claim 1 smell, before Symbol wherein includes a battery as a power supply facility for each category, the form of the battery of the battery belonging to the reactor pressure vessel to a section other than the two sections having a heat removal system is another classification Reactor safety equipment, which is a different form. In Claim 1 or Claim 2, the pool of the isolation capacitor system provided outside the reactor containment vessel, the region below the water level of the pool, and the gas phase region in the reactor containment vessel are connected. 3 pipes, a second motor-operated valve that is provided in the third pipe and interrupts the flow in the third pipe, a gas phase region of a pressure suppression chamber provided in the reactor containment vessel, and the reactor A fourth pipe that communicates with the outside of the containment vessel; a third motor-operated valve that connects and disconnects the flow in the fourth pipe to the fourth pipe; the power supply to the second motor-operated valve; 3. Reactor safety equipment provided with a containment vessel vent facility as the power source equipment of the above-mentioned category, which is different from the power supply to the motor-operated valve .   4. The reactor containment vessel vent system according to claim 3, wherein the reactor containment vessel venting device is configured to control the second motor operated valve to open the second motor operated valve under a condition in which the pressure in the reactor containment vessel is preset. Reactor safety equipment. In Claim 1 or Claim 2 or Claim 3, the 5th piping which connects the inside of the pool of the pressure suppression room provided in the above-mentioned reactor containment vessel, and the inside of the above-mentioned reactor pressure vessel, and the 5th piping A pump that is equipped to drive water in the fifth pipe, a heat exchanger that is equipped in the fifth pipe to cool the water, and an intermittent flow in the fifth pipe that is equipped in the fifth pipe. Two residual heat removal systems having a fourth motor operated valve;
With the power supply equipment of the section different from each other power supply power to each fourth motor operated valve in each residual heat removal system,
The first motor valve, the third motor valve, and the fourth motor valve are configured such that the water level in the reactor pressure vessel is secured at a preset water level, and the pressure in the reactor containment vessel is A control device that opens on condition that the set pressure is high and the water temperature of the pool of the pressure suppression chamber is a preset high temperature,
Reactor safety equipment comprising a configuration in which the control device manually opens the first motor-operated valve, the third motor-operated valve, and the fourth motor-operated valve.   In Claim 5, the preset high pressure is the highest set pressure in the reactor containment vessel in which the nuclear reactor is operated, and the preset high temperature is that of the pool in which the nuclear reactor is operated. Reactor safety equipment with the highest set water temperature.

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