JP2017067494A - Nuclear reactor water injection device and nuclear reactor power generation plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nuclear reactor water injection device capable of stably cooling a reactor core for a long period during reactor isolation by suppressing a battery consumption accompanied with a flow control of a steam turbine type pump.SOLUTION: A nuclear reactor water injection device includes: an emergency signal generation device 25 for generating an emergency signal 33 when two states of a nuclear reactor scram and a loss-of total AC current source event are detected in the situation where no dry well pressure high signal is detected; a decay heat amount calculation device 26a for calculating a decay heat amount generated in a nuclear reactor pressure vessel 2; a target flow amount calculation device 27a for calculating a target flow amount of a steam turbine type pump 17 based on a water temperature 34 measured by a thermometer 21 and a decay heat amount 36 calculated by the decay heat amount calculation device during generation of the emergency signal 33; and a steam regulator valve control device 28a for adjusting a degree of opening of a steam increasing and decreasing valve 11 based a pressure 37 measured by a pressure meter 18, a rotation number 38 measured by a rotation speed meter 22, and a target flow amount 32 calculated by the target flow amount calculation device.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a nuclear reactor water injection apparatus and a nuclear power plant, and more particularly to a nuclear reactor water injection apparatus and a nuclear power plant suitable for application to a boiling water nuclear power plant.

  Many boiling water nuclear power plants have a reactor isolation system (RCIC) consisting of a reactor water injection system using a steam turbine pump as one of the water injection systems. Yes. The reactor isolation cooling system is used when the reactor is scrammed due to any abnormality occurring in the nuclear power plant, and when the reactor pressure vessel is isolated and the water supply to the reactor pressure vessel is stopped, This is one of the facilities to prevent fuel damage by pouring water. Nuclear power plants usually have a dynamic water injection system that uses an electric pump in addition to the reactor isolation cooling system, but the reactor isolation cooling system is an electric pump that loses all AC power. Even in a situation where the battery does not operate, it is possible to operate only by direct current power supply from the battery. For example, Patent Documents 1 and 2 disclose such a reactor water injection device as a reactor isolation cooling system.

  First, the operation of the reactor water injection device described in Patent Document 1 will be described with reference to FIG. When the control rod 3 is inserted into the core 1 at the time of reactor isolation, the nuclear fission chain reaction stops and the reactor power is greatly reduced. However, steam is generated from the core 1 due to the decay heat generated by the decay of radionuclides. to continue. The generated steam is led to the pressure suppression pool, which is the condensing water source 12, via the main steam relief valve 7, and condensed, thereby preventing overpressure damage of the reactor pressure vessel 2. When steam flows out through the main steam relief valve 7 and the water level H in the reactor pressure vessel gradually decreases and falls below a preset lower limit water level, the steam turbine pump 17 is activated. That is, after the turbine stop valve 10 is fully opened, the opening of the steam control valve 11 is adjusted, and the steam generated in the core 1 is guided to the steam turbine 8 to perform work, and then enters the pressure suppression pool that is the condensing water source 12. Exhaust and condensed. By driving the steam turbine pump 17 by the work recovered by the steam turbine 8, the water in the condensate storage tank as the pumping water source 15 can be poured into the reactor pressure vessel 2. Thereby, the decrease in the water level H in the reactor pressure vessel stops, and the cooling function of the core 1 can be maintained.

  Here, in the reactor water injection device 100, the opening degree of the steam control valve 11 is controlled so that the water injection flow rate of the steam turbine pump 17 coincides with the preset rated flow rate. Is larger than the amount of steam generated by decay heat and flowing out of the main steam relief valve 7, the water level H in the reactor pressure vessel starts to rise after the steam turbine pump 17 is started. Therefore, although not described in Patent Document 1, when the water pressure H in the reactor pressure vessel exceeds a preset stop water level, a steam turbine pump is used to prevent the liquid phase coolant from flowing into the steam turbine 8. 17 needs to be stopped. After the steam turbine pump 17 is stopped, the steam generated in the reactor core 1 flows out through the main steam relief valve 7, so that the water pressure H in the reactor pressure vessel starts to decrease again. By repeating the operation as described above, the pressure level in the reactor pressure vessel 2 is controlled below the design limit value by the steam discharge from the main steam relief valve 7, while the water level H in the reactor pressure vessel is stopped and stopped. Repeat rising and falling between water levels. Thereby, the water level H in the reactor pressure vessel is maintained within a certain range, and the reactor core 1 can be stably cooled without exposing it to the water surface.

  On the other hand, in the reactor water injection device 100 described in Patent Document 2, the turbine stop valve 10 is opened when the reactor is isolated, and the steam control valve is set so that the deviation between the water pressure H in the reactor pressure vessel and the water level set value becomes zero. 11 is adjusted. Thereby, the water level H in the reactor pressure vessel is kept constant, and the reactor core 1 can be stably cooled without exposing it to the water surface.

JP 2012-233724 A JP 58-180998 A

  However, in the reactor water injection apparatus described in Patent Document 1, since the water injection flow rate by the steam turbine pump 17 is constant at the rated flow rate, the battery consumption associated with driving the steam control valve 11 is small, but the turbine stop valve 10 is frequently used. Therefore, battery consumption associated with driving of the turbine stop valve 10 is large.

  On the other hand, in the reactor water injection device described in Patent Document 2, since the turbine stop valve 10 is opened only once, the battery consumption associated with driving the turbine stop valve 10 is small, but the opening of the steam control valve 11 is changed to the water level. In order to follow and always adjust, battery consumption accompanying the drive of the steam control valve 11 is large.

  As described above, both of the reactor water injection devices of Patent Documents 1 and 2 consume a large amount of battery accompanying the flow control of the steam turbine pump 17, and there is a possibility that the reactor core 1 cannot be stably cooled for a long time when the reactor is isolated. is there.

  The present invention has been made in view of the above circumstances, and its purpose is to stably cool the core over a long period of time when the reactor is isolated by suppressing the battery consumption associated with the flow control of the steam turbine pump. Is to provide a reliable reactor water injection device.

  In order to solve the above problems, the present invention provides a core capable of generating steam by boiling cooling water using fission reaction heat or decay heat, and having a function of stopping a fission chain reaction by scram, and the core In a nuclear reactor water injection apparatus provided in a nuclear power plant having a reactor pressure vessel containing a reactor and a main steam relief valve for preventing overpressure damage of the reactor pressure vessel. A steam turbine driven by steam; a steam inlet pipe for guiding steam generated in the reactor pressure vessel to the steam turbine; a turbine stop valve provided in the steam inlet pipe; and the steam inlet pipe. A steam control valve that adjusts the flow rate of steam guided to the steam turbine, a condensing water source that condenses steam that has worked in the steam turbine, and the steam A steam exhaust pipe for guiding steam working in a turbine to the condensing water source; a check valve provided in the steam exhaust pipe for preventing a back flow from the condensing water source to the steam turbine; and the reactor pressure vessel A pumping water source for storing cooling water for pouring water therein, a steam turbine pump driven by the steam turbine and for pouring the cooling water of the pumping water source into the reactor pressure vessel, and the reactor pressure A pressure gauge that measures the pressure in the vessel, a water level measuring device that measures the water level in the reactor pressure vessel, a thermometer that measures the water temperature of the pumped water source, and a rotation that measures the number of revolutions of the steam turbine When the water level measured by the speedometer and the water level measuring device falls below a predetermined lower limit water level, a start signal is generated to start the steam turbine pump, and the water level measured by the water level measuring device is predetermined. A start / stop signal generator for generating a stop signal for stopping the steam turbine pump when the stop water level is exceeded, and when the start signal is generated, the turbine stop valve is fully opened to generate the stop signal. A stop valve control device that fully closes the turbine stop valve, and an emergency signal that generates an emergency signal when detecting two states of reactor scram and loss of all AC power in a situation where a high drywell pressure signal is not detected A generator, a decay calorie calculating device for calculating the decay heat generated in the reactor pressure vessel, a water temperature measured by the thermometer when the emergency signal is generated, and a decay heat calculated by the decay calorie calculating device Based on the target flow rate calculation device for calculating the target flow rate of the steam turbine pump, the pressure measured by the pressure gauge and the speed measured by the tachometer. A steam control valve control device that adjusts the opening of the steam control valve based on the rotation number and the target flow rate calculated by the target flow rate calculation device is provided.

  According to the present invention, in a nuclear power plant, it is possible to stably cool the core for a long time at the time of reactor isolation by suppressing battery consumption accompanying flow control of the steam turbine pump.

It is a block diagram of the reactor water injection apparatus which concerns on 1st Example of this invention. It is a block diagram of the reactor water injection apparatus which concerns on a prior art. It is a logic diagram of the emergency signal generator with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a logic diagram of the steam control valve control apparatus with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a logic diagram of the target flow volume calculation apparatus with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a logic diagram of the decay calorie | heat amount calculation apparatus with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a logic diagram of the start / stop signal generator with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a logic diagram of the differential pressure-water level conversion apparatus with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. The reactor water injection device according to the first embodiment of the present invention is operated at the rated flow rate as in the prior art, and the number of start / stop times of the steam turbine pump and the reactor according to the first embodiment of the present invention It is a figure which compares and shows the starting / stop frequency | count of a steam turbine type pump at the time of operating a water injection apparatus with the target flow volume calculated with the target flow volume calculation apparatus. It is a logic diagram of the steam control valve control apparatus (modification) with which the nuclear reactor water injection apparatus which concerns on 1st Example of this invention is provided. It is a block diagram of the reactor water injection apparatus (modification) which concerns on 1st Example of this invention. It is a logic diagram of the starting / stopping signal generator (modification) with which the nuclear reactor water injection device concerning the 1st example of the present invention is provided. It is a logic diagram of the steam control valve control apparatus corresponding to the start / stop signal generator (modification) shown in FIG. It is a block diagram of the reactor water injection apparatus which concerns on the 2nd Example of this invention. It is a logic diagram of the decay | disintegration calorie | heat amount calculation apparatus with which the nuclear reactor water injection apparatus which concerns on 2nd Example of this invention is provided. It is a logic diagram of the target flow volume calculation apparatus with which the reactor water injection apparatus which concerns on 2nd Example of this invention is provided. It is a block diagram of the reactor water injection apparatus which concerns on the 3rd Example of this invention. It is a logic diagram of the differential pressure-water level conversion apparatus with which the nuclear reactor water injection apparatus which concerns on 3rd Example of this invention is provided. It is a logic diagram of the decay | disintegration calorie | heat amount calculation apparatus with which the nuclear reactor water injection apparatus which concerns on 3rd Example of this invention is provided. It is a block diagram of the reactor water injection apparatus which concerns on the 4th Example of this invention. It is a logic diagram of the water source selection apparatus with which the nuclear reactor water injection apparatus which concerns on 4th Example of this invention is provided. It is a block diagram of the reactor water injection apparatus which concerns on the 5th Example of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same member and the overlapping description is abbreviate | omitted suitably.

  As a first embodiment of the present invention, an example in which the present invention is applied to a reactor water injection device as a cooling system for isolating a reactor of a boiling water nuclear power plant will be described.

  FIG. 1 shows the configuration of a reactor water injection apparatus according to a first embodiment of the present invention. In a boiling water nuclear power plant, a reactor core 1 loaded with a plurality of fuel assemblies (not shown) is contained in a reactor pressure vessel 2. A control rod 3 is provided in the reactor pressure vessel 2 for quickly reducing the reactor power at the time of reactor isolation. A main steam pipe 4 and a water supply pipe (not shown) are connected to the reactor pressure vessel 2. A main steam isolation valve 5 is installed in the main steam pipe 4, and a pipe branching from the main steam pipe 4 (hereinafter referred to as “main steam relief pipe”) 6 has an excess during isolation of the reactor pressure vessel 2. A main steam relief valve 7 is installed to prevent pressure damage.

  The reactor water injection device 100a according to the present embodiment includes a steam turbine 8 driven by steam generated in the reactor pressure vessel 2, and a steam inlet pipe that guides the steam generated in the reactor pressure vessel 2 to the steam turbine 8. 9, a turbine stop valve 10 provided in the steam inlet pipe 9, a steam control valve 11 provided in the steam inlet pipe 9 for adjusting the flow rate of the steam guided to the steam turbine 8, and the steam turbine 8. A condensing water source 12 that condenses the steam, a steam exhaust pipe 13 that guides the steam that has worked in the steam turbine 8 to the condensing water source 12, and a backflow from the condensing water source 12 to the steam turbine 8. Check valve 14, a pumping water source 15 for storing cooling water for pouring water into the reactor pressure vessel 2, and a pumping water source 15 driven by the steam turbine 8 and via the water injection pipe 16. Cooling water and a steam turbine pump 17 to the water injection into the reactor pressure vessel 2. The above configuration is the same as that of the reactor water injection device as the reactor isolation cooling system according to the prior art shown in FIG.

  Reactor water injection apparatus 100a according to the present embodiment, as an instrumentation system for monitoring the state of each apparatus, pressure gauge 18 for measuring the pressure in reactor pressure vessel 2, and differential pressure between water level H in reactor pressure vessel A differential pressure gauge 19 for measuring, a thermometer 20 for measuring the water temperature of the pumped water source 15, and a tachometer 22 for measuring the rotation speed of the steam turbine 8 are provided. In addition, the reactor water injection device 100a is a control system for controlling the operation of each device, such as a differential pressure-water level conversion device 22a, a start / stop signal generation device 23a, a stop valve control device 24, an emergency signal generation device 25, a decay heat quantity. A calculation device 26a, a target flow rate calculation device 27a, and a steam control valve control device 28a are provided.

  The reactor water injection apparatus of the present invention does not require an AC power supply, but requires a DC power supply for opening / closing valves and controlling each apparatus. As a situation where it is necessary to prevent the battery that is one of the DC power supplies from being consumed, the loss of all AC power supplies is assumed. In other words, if AC power can be used by starting an external power supply or emergency generator, the AC power can be converted to DC power and the reactor water injection device can be used, and it can be driven by an AC power source other than the reactor water injection device. Since it is possible to use a water injection system and a heat removal system using an electric pump, there is no need to prevent battery consumption. On the other hand, if all AC power is lost, the DC power may be only the battery and the water injection means may be only the reactor water injection device. It is necessary to maintain the core cooling by continuing to operate the reactor water injection system while extending the battery life as long as possible until the arrival of support supplies from the plant.

  Hereinafter, the operation of the reactor water injection device 100a at the time of occurrence of loss of all AC power will be described.

  First, the system operation will be described. When all AC power is lost, the coolant recirculation pump stops due to AC power loss, and the main steam isolation valve 5 is closed by a main condenser vacuum low signal, etc. Isolated. Further, a scram signal is generated by a main steam isolation valve closing signal, a reactor water level low signal, or the like, and the control rod 3 is inserted into the reactor core 1. Although the fission chain reaction is stopped by the insertion of the control rod 3 and the reactor power rapidly decreases, steam continues to be generated from the reactor core 1 due to the decay heat generated by the decay of the radionuclide. The generated steam is discharged out of the reactor pressure vessel 2 through the main steam relief valve 7, thereby preventing overpressure damage of the reactor pressure vessel 2. When steam flows out through the main steam relief valve 7 and the water level H in the reactor pressure vessel gradually decreases and falls below a preset lower limit water level, the steam turbine pump 17 is activated. That is, the turbine stop valve 10 and the steam control valve 11 are opened, and the steam generated in the core 1 is guided to the steam turbine 8 through the steam inlet pipe 9 to work, and then the water source for condensation is supplied through the steam exhaust pipe 13. 12 is exhausted and condensed. The coolant of the pumping water source 15 is injected into the reactor pressure vessel 2 through the water injection pipe 16 by driving the steam turbine pump 17 by work recovered by the steam turbine 8. Further, the decay heat quantity 36 and the target flow rate 32 at the start time of the steam turbine pump 17 are calculated, and the opening degree of the steam control valve 11 is controlled so that the water injection flow rate into the reactor pressure vessel 2 matches the required water flow rate. To do. Thereby, the decrease in the water level H in the reactor pressure vessel stops, and the cooling function of the core 1 can be maintained.

  Next, the operation of each device for realizing the system operation will be described. The start / stop of the steam turbine pump 17 is controlled based on the water level 30 calculated by the differential pressure / water level converter 22a. Specifically, the differential pressure-water level conversion device 22 a converts the differential pressure 29 of the reactor pressure vessel water level H measured by the differential pressure gauge 19 into the water level 30 in the reactor pressure vessel 2. The start / stop signal generator 23a outputs a start signal for starting the steam turbine pump 17 when the water level 30 falls below a preset lower limit water level, and the water level 30 is set to a preset stop water level. When it exceeds, a stop signal for stopping the steam turbine pump 17 is output (the start signal and the stop signal are collectively indicated by a start / stop signal 31). The stop valve control device 24 fully opens and closes the turbine stop valve 10 based on the start / stop signal 31. Further, while the steam turbine pump 17 is activated, the steam control valve control device 28a adjusts the opening of the steam control valve 11 so that the water injection flow rate by the steam turbine pump 17 matches the target flow rate. When the AC power supply can be used, that is, when the emergency signal generator 25 is not activated, the target flow rate calculation device 27a is not activated, and the target flow rate 32 is not input to the steam control valve control device 28a. In this case, the steam control valve control device 28a adjusts the opening of the steam control valve 11 so that the flow rate of water injected by the steam turbine pump 17 matches the preset rated flow rate.

  On the other hand, when all AC power is lost, scrum is successful, and reactor isolation is successful, the emergency signal generator 25 generates an emergency signal 33, thereby starting the target flow rate calculation device 27a. The target flow rate calculation device 27a receives the decay heat quantity 36 in the reactor pressure vessel 2 and the water temperature 34 of the pumped water source 15 and outputs a target flow rate 32. The steam control valve control device 28a is a valve opening / closing torque 35 for adjusting the opening of the steam control valve 11 so that the water injection flow rate by the steam turbine pump 17 matches the target flow rate 32 calculated by the target flow rate calculation device 27a. Is output. The decay heat quantity 36 input to the target flow rate calculation device 27a is calculated by the decay heat quantity calculation device 26a. The decay heat quantity calculation device 26a utilizes the fact that the rate of change in the water level in the reactor pressure vessel 2 is due to evaporation due to decay heat, and the water level calculated by the pressure 37 measured by the pressure gauge 18 and the differential pressure-water level conversion device 22a. 30 is input, and the decay heat quantity 36 is output.

  Next, the logic of each device will be described in detail with reference to the drawings.

  FIG. 3 shows the logic of the emergency signal generator 25. Since the reactor water injection device 100a exhibits performance only when all AC power is lost, when scram is successful, and when reactor isolation is successful, the logic that generates the emergency signal 33 when all of these signals are detected. And In addition, when a loss of coolant accident (LOCA) occurs, that is, when the reactor pressure vessel 2 is ruptured, it flows out of the rupture port of the reactor pressure vessel 2 in addition to a decrease in water volume due to water evaporation due to decay heat. The rate of decrease in the water level H in the reactor pressure vessel increases by the amount of coolant to be increased. In the situation where LOCA has occurred, the steam turbine according to the present invention has a different mechanism for reducing the water level in the reactor pressure vessel due to water evaporation and in the reactor pressure vessel due to outflow from the break opening. The amount of water injected by the pump 17 is insufficient, the core 1 is exposed on the water surface, and the fuel may be damaged. Therefore, the logic for generating the emergency signal 33 is set only when the dry well pressure high signal which is a general LOCA signal is not generated. The emergency signal 33 generated by the emergency signal generator 25 is input to the target flow rate calculation device 27a.

  FIG. 4 shows the logic of the steam control valve control device 28a. The steam control valve control device 28a receives the start / stop signal 31 of the steam turbine pump 17, the rotational speed 38 of the steam turbine 8, the pressure 37 in the reactor pressure vessel 2, and the target flow rate 32 of the steam turbine pump 17. The valve opening / closing torque 35 for adjusting the opening degree of the steam control valve 11 is output. This will be specifically described below. When the activation signal 31-1 is input to the activation / stop control unit 28a-1 of the steam control valve control device 28a, the valve opening degree adjustment unit 28a-2 of the steam control valve control device 28a is activated. The valve opening adjustment unit 28 a-2 indirectly controls the flow rate of water injected by the steam turbine pump 17 by controlling the rotation speed of the steam turbine 8 that is a drive source of the steam turbine pump 17. The relationship between the water injection flow rate, the pressure in the reactor pressure vessel, and the rotational speed of the turbine is held in the valve opening adjustment unit 28a-2 as a table. By inputting the target flow rate 32 and the pressure 37, the steam turbine A target rotational speed of 8 is calculated. Note that when the emergency signal 33 is not generated, the target flow rate 32 is not input, so the target rotational speed is calculated using a preset rated flow rate. Next, the rotation speed 38 is compared with the target rotation speed. When the rotational speed 38 is lower than the target rotational speed, a positive input is input to the torque generator, the rotational speed 38 is increased by operating the steam control valve 11 in the opening direction, and the rotational speed 38 is brought close to the target rotational speed. . In the opposite case, the rotation speed 38 is decreased by operating the steam control valve 11 in the closing direction, and the rotation speed 38 is brought close to the target rotation speed.

  The turbine stop valve 10 installed on the upstream side of the steam control valve 11 is controlled by a stop valve control device 24. The logic of the stop valve control device 24 opens the turbine stop valve 10 when the start signal 31-1 is input from the start / stop signal generator 23a, and turns off the turbine stop valve 10 when the stop signal 31-2 is input. It is as simple as fully closing. Since the turbine stop valve 10 has a fully open / closed control logic, when the turbine stop valve 10 is frequently opened and closed, DC power is consumed as the turbine stop valve 10 is driven.

  FIG. 5 shows the logic of the target flow rate calculation device 27a. The target flow rate calculation device 27a receives the emergency signal 33, the decay heat quantity 36 in the reactor pressure vessel 2, and the water temperature 34 of the pumped water source 15 and outputs the target flow rate 32 of the steam turbine pump 17. This will be specifically described below. When the emergency signal 33 is input to the activation / stop control unit 27a-1 of the target flow rate calculation device 27a, the target flow rate calculation unit 27a-2 of the target flow rate calculation device 27a is activated. The target flow rate calculation unit 27a-2 calculates and outputs the target flow rate 32 only when both the decay heat quantity 36 and the water temperature 34 are input. The water temperature 34 of the pumping water source 15 is used to calculate the coolant enthalpy of the pumping water source 15. The coolant enthalpy has almost no pressure dependency, but has a large temperature dependency. Therefore, an approximate calculation is performed from the measured water temperature assuming a linear function. On the other hand, since the pressure dependency of saturated steam enthalpy is small, a set value (2790 kJ / kg) is used. A result obtained by dividing the value of the decay heat quantity 36 by the difference between the saturated steam enthalpy and the coolant enthalpy of the pumped water source 15 is output as the target flow rate 32.

  FIG. 6 shows the logic of the decay heat quantity calculation device 26a. The decay heat amount calculation device 26 a receives the start / stop signal 31 of the steam turbine pump 17, the pressure 37 in the reactor pressure vessel 2 and the water level 30 and outputs the decay heat amount 36 in the reactor pressure vessel 2. This will be specifically described below. The decay heat quantity calculation device 26a calculates the decay heat quantity 36 by multiplying the four physical quantities of the water level change rate, the saturated water density, the channel area occupied by the coolant in the reactor pressure vessel 2, and the latent heat of vaporization. Since the water level change rate is measured in order to evaluate the amount of water evaporation due to decay heat, it cannot be measured during the water injection by the steam turbine pump 17, and the water level H in the reactor pressure vessel decreases. Therefore, it is necessary to calculate at the timing when the steam turbine pump 17 is stopped. In order to enable selection of the measurement timing, the decay calorie calculation device 26a sets the internal variables F1 and F2 to 1 and changes the water level when the start signal 31-1 is input from the start / stop signal generator 23a. Turn off the rate calculation routine. On the other hand, when the stop signal 31-2 is input, the water level change rate calculation routine is turned on by setting 0 to each of the internal variables F1 and F2. The water level change rate is calculated by dividing the water level difference between two set water levels (upper water level and lower water level) by the time difference when the water level H in the reactor pressure vessel crosses the two water level set points. The time difference is measured by a built-in timer of the decay heat quantity calculation device 26a. The upper water level is set below the stop water level of the steam turbine pump 17, and the lower water level is set above the startup water level of the steam turbine pump 17. In the reactor pressure vessel 2 of the boiling water nuclear power plant, reactor structures (not shown) such as separators, dryers, and shrouds are installed, and the flow occupied by the coolant in the reactor pressure vessel 2 Although the road area takes different values in the height direction, there is a region that can be regarded as a substantially constant flow path area, such as a stand pipe portion directly under the separator. For example, if the upper water level is set to the upper end height of the standpipe area and the lower water level is set to the lower end height of the standpipe area, the flow area that should be multiplied by the water level change rate when calculating the decay heat quantity is geometrically calculated. The convenience can be improved. The latent heat of vaporization and the saturated water density of the coolant in the reactor pressure vessel 2 are generally functions of the pressure in the reactor pressure vessel, and the evaporation corresponding to the pressure 37 is performed by interpolating a prepared table. Calculate latent heat and saturated water density.

  FIG. 7 shows the logic of the start / stop signal generator 23a. The start / stop signal generator 23a outputs the start / stop signal 31 (start signal 31-1 or stop signal 31-2) of the steam turbine pump 17 with the water level 30 in the reactor pressure vessel 2 as an input. This will be specifically described below. The water level 30 input to the start / stop signal generator 23a is compared in magnitude with the start water level and the stop water level of the steam turbine pump 17, respectively. When the value of the water level 30 falls below the startup water level, the startup signal 31-1 of the steam turbine pump 17 is generated in order to prevent exposure of the core 1 to the water surface. On the other hand, when the water level 30 exceeds the stop water level, the stop signal 31-2 of the steam turbine pump 17 is generated in order to prevent the steam turbine 8 from being damaged due to the coolant flowing into the reactor pressure vessel 2. In order to achieve the above functions, the starting water level is installed below the stopping water level. Specifically, the water level at which the startup water level is added to the upper water level of the core 1 to prevent exposure of the core 1 to the water surface, and the stop water level prevent coolant from flowing into the steam turbine 8. The water level required to do this is set to a water level that is reduced from the height of the steam inlet pipe to the steam turbine 8.

  FIG. 8 shows the logic of the differential pressure / water level converter 22a. The differential pressure-water level conversion device 22a receives the differential pressure 29 and the pressure 37 in the reactor pressure vessel 2 and outputs the water level 30 in the reactor pressure vessel 2. This will be specifically described below. After the differential pressure 29 is divided by the product of the saturated water density and the gravitational acceleration, the differential pressure-water level conversion device 22a reduces the reference water level deviation ΔH (= Hs−Hp) for conversion to the relative water level from the reference water level Hs. Thus, the water level 30 from the reference water level Hs is calculated. Gravitational acceleration is held as a set value. The reference water level deviation ΔH is also held as a set value because it is uniquely determined if the reference water level Hs and the installation water level Hp of the differential pressure gauge 19 are determined. Since the saturated water density is highly pressure dependent, an approximate calculation is performed from the measured pressure by interpolating a table prepared in advance.

  FIG. 9 shows the number of times the steam turbine pump 17 is started and stopped when the steam turbine pump 17 is operated at the rated flow rate as in the prior art, and the target flow rate calculated by the target flow rate calculation device 27a. The number of start / stop times of the steam turbine pump 17 when operated at 32 is shown in comparison. The horizontal axis in the figure represents the elapsed time, and the vertical axis represents the water injection flow rate of the steam turbine pump 17. The operation period was assumed to be 2 weeks. In the figure, since the region where the flow rate is 0 represents the stop state of the steam turbine pump 17, the number of times the flow rate becomes 0 corresponds to the number of stops of the steam turbine pump 17. As shown in the figure, the steam turbine pump 17 was started and stopped 46 times when operated at the rated flow rate, whereas the steam turbine when operated at the target flow rate calculated by the target flow rate calculation device 27a. The number of times the pump 17 was started and stopped was 5 times.

  As described above, according to the present embodiment, the target flow rate that is substantially balanced with the amount of coolant lost in the reactor pressure vessel 2 due to decay heat is calculated at the time of reactor isolation, and the water injection flow rate of the steam turbine pump 17 is calculated as follows. By controlling so as to coincide with the target flow rate, the frequency of opening and closing the turbine stop valve 10 is reduced. Further, since the target flow rate is constant during the startup of the steam turbine pump 17, the time for adjusting the opening degree of the steam control valve 11 is almost limited immediately after the startup of the steam turbine pump 17. As a result, battery consumption associated with the driving of the turbine stop valve 10 and the steam control valve 11 is suppressed, and the core 1 can be stably cooled over a long period of time.

  Further, the steam control valve control device 28b of FIG. 10 can be used instead of the steam control valve control device 28a of FIG. The steam control valve control device 28b of FIG. 10 differs from the steam control valve control device 28a of FIG. 4 in that a built-in timer is added to the start / stop control unit 28b-1 of the steam control valve control device 28b. That is, the start / stop control unit 28b-1 measures the elapsed time since the start of the steam control valve control device 28a by the built-in timer, and stops the valve opening degree control unit 28b-2 at the timing when 30 seconds have elapsed. . There are two reasons why control is stopped in 30 seconds. One is that, in the reactor water injection device as a cooling system for reactor isolation according to the prior art, the flow control by the opening control of the steam control valve is almost completed within 30 seconds. What can be expected is that the amount of water injected by the steam turbine pump 17 of the present invention is almost balanced with the amount of coolant lost in the reactor pressure vessel 2 due to decay heat. Therefore, the pressure in the reactor pressure vessel 2 is almost fixed in the vicinity of the set pressure of the main steam relief valve 7, so that the pressure in the reactor pressure vessel 2 is injected into the steam turbine pump 17. The influence on the flow rate is small, and the required water injection flow rate for cooling the core 1 is relatively stable. By using the steam control valve control device 28b of FIG. 10, it becomes possible to suppress the battery consumption accompanying the detailed control of the steam control valve 11 after 30 seconds from the start by the valve opening control unit 28b-2, and further battery Expected to reduce consumption. The stop timing of the valve opening adjusting unit 28b-2 can be set to any time longer than 30 seconds.

  Further, instead of separately providing the pumping water source 15 and the condensing water source 12 as shown in FIG. 1, a condensing / pumping water source 39 that integrates the pumping water source and the condensing water source as shown in FIG. A configuration provided is also conceivable. In that case, a more compact nuclear power plant can be realized.

  Further, instead of the start / stop signal generating device 23a of FIG. 7 and the steam control valve control device 28a of FIG. 4, the start / stop signal generating device 23b of FIG. 12 and the steam control valve control device 28c of FIG. 13 may be used. it can. The start / stop signal generator 23a of FIG. 12 differs from the start / stop signal generator of FIG. 7 in that the water level 30 in the reactor pressure vessel 2 is set lower than the start water level of the steam turbine pump 17. The point is that an abnormal signal 31-3 is output when the water level falls below. Correspondingly, processing logic when the abnormal signal 31-3 is input as the start / stop signal 31 is added to the steam control valve control device 28c of FIG. Specifically, when the abnormal signal 31-3 is input as the start / stop signal 31, the valve opening degree control unit 28c-2 sets in advance instead of the target flow rate 32 input from the target flow rate calculation device 27a. The target rotational speed is calculated using the rated flow rate. In general, the rated flow rate is set to be larger than the decay heat level, so that the flooding of the core 1 can be maintained even from the water level (abnormal water level) where the abnormal signal 31-3 is generated. In this way, by using the start / stop signal generating device 23b of FIG. 12 and the steam control valve control device 28c of FIG. 13, the target flow rate 32 calculated by the target flow rate calculation device 27a should be used to maintain the flooding of the core 1. Even if it is insufficient, the flooding of the reactor core 1 can be maintained, so that the reliability of the reactor water injection device 100a can be improved.

  The reactor water injection apparatus according to the second embodiment of the present invention will be described focusing on differences from the first embodiment.

  FIG. 14 shows the configuration of a reactor water injection apparatus according to the second embodiment of the present invention. In the reactor water injection device 100b according to the present embodiment, the emergency signal 33 output from the emergency signal generator 25 is input to the timer 40, and only the elapsed time 41 of the timer 40 is input to the decay heat quantity calculation device 26b. The flow rate calculation device 27b is different from the first embodiment in that only the decay heat amount 36 calculated by the decay heat amount calculation device 26b and the water temperature 34 measured by the thermometer 20 are input.

  Hereinafter, the operation of the reactor water injection device 100b when the loss of all AC power is generated will be described.

  Since the system operation is the same as that of the first embodiment, description thereof is omitted.

  The operation of each device for realizing the system operation will be described with respect to the timer 40, the decay heat amount calculation device 26b, and the target flow rate calculation device 27a, which are different from the first embodiment. When all AC power is lost, scrum is successful, and reactor isolation is successful, the emergency signal generator 25 is activated to generate an emergency signal 33, and the emergency signal 33 is input to start the timer 40. The timer 40 is a device that measures the elapsed time after the occurrence of the scrum, and once activated, continues to output the elapsed time 41 until the battery is depleted. The decay heat quantity calculation device 26b uses the fact that the decay heat quantity is a function of the elapsed time after scram generation, and outputs the decay heat quantity 36 with the elapsed time 41 as an input. The target flow rate calculation device 27b in the present embodiment has only a configuration corresponding to the target flow rate calculation unit 27a-2 of the target flow rate calculation device 27a in the first embodiment, and corresponds to the start / stop control unit 27a-1. This is different from the first embodiment in that it does not have a configuration to do so.

  Next, the logic of each device will be described in detail with reference to the drawings. Since the timer 40 is as described above, the description thereof is omitted.

  FIG. 15 shows the logic of the decay heat quantity calculation device 26b. The decay heat quantity calculation device 26 b receives the elapsed time 41 of the timer 40 and outputs the decay heat quantity 36 in the reactor pressure vessel 2. This will be specifically described below. The decay heat quantity calculation device 26a (see FIG. 6) in the first embodiment utilizes the fact that the water level change rate in the reactor pressure vessel 2 is caused by evaporation due to decay heat, and the pressure 37 in the reactor pressure vessel 2 And the water level 30 is input, and the decay heat quantity 36 is output. On the other hand, the decay heat quantity calculation device 26b of the present embodiment uses the fact that the decay heat quantity is a function of the elapsed time after scram generation, and outputs the decay heat quantity 36 with the elapsed time 41 as an input. Here, the decay heat quantity is a function of the elapsed time (cooling period) after the occurrence of the scram and also a function of the fuel composition and the irradiation period. Therefore, when adopting this method, it is necessary to evaluate the decay heat quantity in advance for the fuel loaded in the core during the operation cycle, and make a table of the evaluation results and hold it in the decay heat quantity calculation device 26b. There is.

  FIG. 16 shows the logic of the target flow rate calculation device 27b. The target flow rate calculation device 27b receives the decay heat quantity 36 in the reactor pressure vessel 2 and the water temperature 34 of the pumped water source 15 and outputs a target flow rate 32. The target flow rate calculation device 27b in this embodiment is different from the target flow rate calculation device 27a (see FIG. 5) in the first embodiment in that it is not necessary to input the emergency signal 33. That is, the target flow rate calculation device 27a in the first embodiment is activated by the emergency signal 33, but the decay heat quantity 36 in the present embodiment also serves as the emergency signal 33, so the target flow rate calculation device in the present embodiment. 27 b does not have a configuration corresponding to the start / stop control unit 27 a-1 that starts and stops the target flow rate calculation unit 27 a-2 based on the emergency signal 33.

  Also in the present embodiment, as in the first embodiment, battery consumption associated with driving of the turbine stop valve 10 and the steam control valve 11 is suppressed, and the core 1 can be stably cooled over a long period of time. . Furthermore, by calculating the decay heat quantity 36 using the elapsed time 41 after scram generation, the configuration of the decay heat quantity calculation device 26b and the target flow rate calculation device 27b is simplified.

  A reactor water injection apparatus according to a third embodiment of the present invention will be described focusing on differences from the first embodiment.

  FIG. 17 shows the configuration of a reactor water injection apparatus according to the third embodiment of the present invention. The reactor water injection device 100c in the present embodiment is different from the first embodiment in that the pressure 37 measured by the pressure gauge 18 is not input to the differential pressure-water level conversion device 22b and the decay heat amount calculation device 26c.

  Hereinafter, the operation of the reactor water injection device 100c when the loss of all AC power is generated will be described.

  Since the system operation and the operation of each device for realizing the system operation are the same as those in the first embodiment, the description thereof will be omitted, and the logic of each device will be described in detail with reference to the drawings.

  FIG. 18 shows the logic of the differential pressure / water level converter 22b. The differential pressure-water level converter 22b receives the differential pressure 29 in the reactor pressure vessel 2 as an input and outputs the water level 30 in the reactor pressure vessel 2. Hereinafter, differences from the differential pressure / water level converter 22a (see FIG. 8) in the first embodiment will be described in detail. In the differential pressure-water level converter 22a in the first embodiment, the saturated water density is calculated as a function of the pressure 37 in the reactor pressure vessel 2, but in the differential pressure-water level converter 22b in the present embodiment, as a set value. keeping. This is because the flow rate of water injected into the reactor pressure vessel 2 by the steam turbine pump 17 of the present invention is almost balanced with the amount of coolant lost in the reactor pressure vessel 2 due to decay heat. The inside of the reactor pressure vessel 2 is not cooled excessively by water injection, and the pressure 37 in the reactor pressure vessel 2 stabilizes in the vicinity of the set pressure of the main steam relief valve 7, so that the saturated water density is set to the set pressure of the main steam relief valve 7. This is because the error is small even if the corresponding value is fixed.

  FIG. 19 shows the logic of the decay heat quantity calculation device 26c. The decay heat quantity calculation device 26c receives the start / stop signal 31 of the steam turbine pump and the water level 30 in the reactor pressure vessel 2, and outputs the decay heat amount 36 in the reactor pressure vessel 2. Hereinafter, differences from the decay heat quantity calculation device 26a (see FIG. 6) in the first embodiment will be specifically described. In the decay calorie calculation device 26a in the first embodiment, the latent heat of vaporization and the saturated water density of the coolant in the reactor pressure vessel 2 are calculated as functions of the pressure 37 in the reactor pressure vessel 2, respectively. In the decay heat quantity calculation device 26c in FIG. As described above, since the pressure 37 in the reactor pressure vessel 2 is stabilized in the vicinity of the set pressure of the main steam relief valve 7, the latent heat of vaporization and the saturated water density correspond to the set pressure of the main steam relief valve 7, respectively. This is because the error is small even if the value is fixed.

  Also in the present embodiment, as in the first embodiment, battery consumption associated with driving of the turbine stop valve 10 and the steam control valve 11 is suppressed, and the core 1 can be stably cooled over a long period of time. . Furthermore, by fixing the latent heat of vaporization and the saturated water density to values corresponding to the set pressure of the main steam relief valve 7, the configurations of the differential pressure-water level converter 22b and the decay heat quantity calculator 26c are simplified.

  A nuclear reactor water injection apparatus according to a fourth embodiment of the present invention will be described focusing on differences from the first embodiment.

  FIG. 20 shows the configuration of the reactor water injection apparatus according to this embodiment. The reactor water injection device 100d according to the present embodiment replaces the pumping water source 15 and the thermometer 20 in the first embodiment with two pumping water sources 15a and 15b and the two pumping water sources 15a and 15b. Thermometers 20a and 20b for measuring the water temperature, water injection valves 42a and 42b, and a water source selector 43 for performing switching control of the two pumping water sources 15a and 15b are provided.

  Hereinafter, the operation of the reactor water injection device 100d when the loss of all AC power is generated will be described.

  First, the system operation will be described. The operation from the occurrence of loss of all AC power to the start of the steam turbine pump 17 is the same as in the first embodiment. Which of the two pumping water sources 15a and 15b is used depends on the initial setting. For example, if the pumping water source 15a is used, the steam turbine pump 17 driven by the work recovered by the steam turbine 8 is The coolant of the pumping water source 15 a is injected into the reactor pressure vessel 2 through the water injection pipe 16. Thereby, the decrease in the water level H in the reactor pressure vessel stops, and the cooling function of the core 1 is maintained. When it is necessary to switch the water source due to a shortage of the water amount of the pumping water source 15a, a water source selection signal 44 for selecting the pumping water source 15b is input to the water source selecting device 43. Accordingly, the water injection valve 42a is closed and the water injection valve 42b is opened, so that the pumping water source 15b can be used.

  About operation | movement of each apparatus for implement | achieving the said system operation | movement, different from 1st Example, the water sources 15a and 15b for pumping, the thermometers 20a and 20b, the water injection valves 42a and 42b, and the water source selection apparatus 43 are demonstrated. . The water source selector 43 receives the water temperatures 34a and 34b and the water source selection signal 44 of the two pumping water sources 15a and 15b, respectively. The water source selection device 43 is configured to open and close the water injection valves 42a and 42b so that only one of the two pumping water sources 15a and 15b selected by the water source selection signal 44 communicates with the water injection pipe 16. 45b and the water temperature 34a or 34b of the selected pumping water source 15a or 15b is output. For example, when the pumping water source 15b is selected, the water source selecting device 43 includes a valve control signal 45a for fully closing the water injection valve 42a, a valve control signal 45b for fully opening the water injection valve 42b, and a pumping water source 15b. The water temperature 34b is output.

  Next, the logic of the water source selection device 43 will be described in detail with reference to FIG.

  The water source selector 43 receives the water source selection signal 44 and the two water temperatures 34a and 34b as inputs, and outputs two valve control signals 45a and 45b and the water temperature 34. This will be specifically described below. When the water source selection signal 44 is input, it is first determined which of the two pumping water sources 15a and 15b has been selected. When the pumping water source 15a is selected, the selection circuit controls the valve control signal 45a for fully opening the water injection valve 42a, the valve control signal 45b for fully closing the water injection valve 42b, and the water temperature 34a of the pumping water source 15a. Is output. By fully opening the water injection valve 42a and fully closing the water injection valve 42b, the pumping water source 15a can be used, and by outputting the water temperature 34a of the pumping water source 15a to the target flow rate calculation device 27a, the pumping water source 15a is output. Corresponding target flow rate calculation is possible. When the pumping water source 15a is not selected, or when the pumping water source 15b is selected, the selection circuit controls the valve control signal 45a for fully closing the water injection valve 42a and the valve for fully opening the water injection valve 42b. The control signal 45b and the water temperature 34b of the pumping water source 15b are output. When the water injection valve 42b is fully opened and the water injection valve 42a is fully closed, the pumping water source 15b can be used. By outputting the water temperature 34b of the pumping water source 15b to the target flow rate calculation device 27a, the pumping water source 15b is output. Corresponding target flow rate calculation is possible. The water source selection signal 44 may be generated not only by the operator manually but also by logic for switching the water source in response to a signal such as a pumping water source water level low.

  Also in the present embodiment, as in the first embodiment, battery consumption associated with driving of the turbine stop valve 10 and the steam control valve 11 is suppressed, and the core 1 can be stably cooled over a long period of time. . Furthermore, by providing the two pumping water sources 15a and 15b so as to be switchable, the core 1 can be stably cooled over a longer period.

  A nuclear reactor water injection apparatus according to a fifth embodiment of the present invention will be described focusing on differences from the first embodiment.

  FIG. 22 shows the configuration of the reactor water injection apparatus according to this embodiment. The reactor water injection device 100e according to the present embodiment replaces the differential pressure gauge 19 and the differential pressure-water level conversion device 22a in the first embodiment as means for measuring the water level H in the reactor pressure vessel, instead of the reactor pressure vessel. A water level gauge 46 for directly measuring the internal water level H is provided. As the water level meter 46, an ultrasonic sensor, a thermocouple, or the like can be used.

  Also in the present embodiment, as in the first embodiment, battery consumption associated with driving of the turbine stop valve 10 and the steam control valve 11 is suppressed, and the core 1 can be stably cooled over a long period of time. . Furthermore, since the water level gauge 46 for directly measuring the water level H in the reactor pressure vessel is provided, the differential pressure-water level conversion device 22a (see FIG. 1) in the first embodiment is not required, so the reactor water injection device The configuration of 100e is simplified.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, or the configuration of another embodiment can be added to the configuration of one embodiment. Furthermore, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Core, 2 ... Reactor pressure vessel, 3 ... Control rod, 4 ... Main steam piping, 5 ... Main steam isolation valve, 6 ... Main steam relief piping, 7 ... Main steam relief valve, 8 ... Steam turbine, 9 ... Steam inlet piping, 10 ... Turbine stop valve, 11 ... Steam control valve, 12 ... Condensation water source, 13 ... Steam exhaust piping, 14 ... Check valve, 15, 15a, 15b ... Water source for pumping water, 16 ... Water injection piping, 17 ... steam turbine pump, 18 ... pressure gauge, 19 ... differential pressure gauge (water level measuring device), 20, 20a, 20b ... thermometer, 21 ... rotational speed meter, 22, 22a, 22b ... differential pressure-water level conversion device (water level) Measuring device), 23a, 23b ... start / stop signal generator, 24 ... stop valve controller, 25 ... emergency signal generator, 26a, 26b, 26c ... decay heat quantity calculator, 27a, 27b ... target flow rate calculator, 27a -1 ... start / stop control unit, 27 -2 ... Target flow rate calculation unit, 28, 28a, 28b, 28c ... Steam control valve control device, 28a-1, 28b-1, 28c-1 ... Start / stop control unit, 28a-2, 28b-2, 28c- 2 ... Valve opening control unit, 29 ... Differential pressure, 30 ... Water level, 31 ... Start / stop signal, 31-1 ... Start signal, 31-2 ... Stop signal, 31-3 ... Abnormal signal, 32 ... Target flow rate, 33 ... Emergency signal, 34, 34a, 34b ... Water temperature, 35 ... Valve opening / closing torque, 36 ... Decay heat, 37 ... Pressure, 38 ... Revolution, 39 ... Condensation / pumping water source, 40 ... Timer, 41 ... Elapsed time, 42a, 42b ... water injection valve, 43 ... water source selection device, 44 ... water source selection signal, 45a, 45b ... valve control signal, 46 ... water level meter (water level measurement device), 100, 100a, 100b, 100c, 100d, 100e ... atom Water injection device, H ... Atom Pressure vessel water level, Hp ... installation level, Hs ... reference level, [Delta] H ... reference water level deviation.

Claims (11)

A core capable of generating steam by boiling boiling water with fission reaction heat or decay heat, and having a fission chain reaction stop function by scram, a reactor pressure vessel containing the core, and the reactor In a reactor water injection device provided in a nuclear power plant having a main steam relief valve for preventing overpressure damage of a pressure vessel,
A steam turbine driven by steam generated in the reactor pressure vessel;
A steam inlet pipe for guiding the steam generated in the reactor pressure vessel to the steam turbine;
A turbine stop valve provided in the steam inlet pipe;
A steam control valve that is provided in the steam inlet pipe and adjusts a flow rate of steam guided to the steam turbine;
A condensing water source for condensing the steam that has worked in the steam turbine;
A steam exhaust pipe for guiding the steam working in the steam turbine to the water source for condensation;
A check valve provided in the steam exhaust pipe to prevent a backflow from the water source for condensation to the steam turbine;
A pumping water source for storing cooling water for pouring water into the reactor pressure vessel;
A steam turbine pump that is driven by the steam turbine and injects cooling water of the pumped water source into the reactor pressure vessel;
A pressure gauge for measuring the pressure in the reactor pressure vessel;
A water level measuring device for measuring the water level in the reactor pressure vessel;
A thermometer for measuring the water temperature of the pumping water source;
A tachometer for measuring the rotation speed of the steam turbine;
When the water level measured by the water level measuring device falls below a predetermined starting water level, an activation signal for starting the steam turbine pump is generated, and the water level measured by the water level measuring device is set above the starting water level. A start / stop signal generator for generating a stop signal for stopping the steam turbine pump when a predetermined stop water level is exceeded;
A stop valve control device that fully opens the turbine stop valve when the start signal is generated and fully closes the turbine stop valve when the stop signal is generated;
An emergency signal generator for generating an emergency signal when detecting two states of scram and loss of all AC power in a situation where a dry well pressure high signal is not detected;
A decay heat quantity calculation device for calculating the decay heat quantity generated in the reactor pressure vessel;
A target flow rate calculation device for calculating a target flow rate of the steam turbine pump based on the water temperature measured by the thermometer and the decay heat amount calculated by the decay heat amount calculation device when the emergency signal is generated;
A steam control valve control device that adjusts the opening of the steam control valve based on the pressure measured by the pressure gauge, the rotational speed measured by the tachometer, and the target flow rate calculated by the target flow rate calculation device. A reactor water injection apparatus characterized by comprising: In the reactor water injection device according to claim 1,
The decay heat quantity calculation device calculates decay heat quantity in the reactor pressure vessel based on a water level measured by the water level measurement device and a pressure measured by the pressure gauge when the activation signal is generated. Reactor water injection equipment. In the reactor water injection device according to claim 1,
The decay heat quantity calculation device calculates a decay heat amount in the reactor pressure vessel based on a water level measured by the water level measurement device when the activation signal is generated. In the reactor water injection device according to any one of claims 1 to 3,
A timer for measuring an elapsed time after the emergency signal is generated;
The decay heat quantity calculation device calculates the decay heat quantity based on the elapsed time measured by the timer,
The target flow rate calculation device calculates a target flow rate of the steam turbine pump based on a water temperature measured by the thermometer and a decay heat amount calculated by the decay heat amount calculation device. . In the reactor water injection device according to any one of claims 1 to 4,
The said steam control valve control apparatus stops the adjustment of the opening degree of the said steam control valve after 30 second or more after starting, The reactor water injection apparatus characterized by the above-mentioned. In the reactor water injection device according to any one of claims 1 to 5,
The water level measuring device has a differential pressure gauge that measures the differential pressure of the water level in the reactor pressure vessel, and based on the pressure measured by the pressure gauge and the differential pressure measured by the differential pressure gauge, Reactor water injection device that calculates the water level in a pressure vessel. In the reactor water injection device according to any one of claims 1 to 6,
The water injection device according to claim 1, wherein the water level measuring device is a water level meter provided in the reactor pressure vessel. The reactor water injection device according to any one of claims 1 to 7,
When the water level measured by the water level measurement device falls below the abnormal water level set below the startup water level of the reactor water injection device, the steam control valve control device sets the target flow rate calculated by the target flow rate calculation device. Instead, the reactor water injection apparatus is characterized in that the opening of the steam control valve is adjusted based on a preset rated flow rate. In the reactor water injection device according to any one of claims 1 to 8,
The pumping water source has a first pumping water source and a second pumping water source,
The thermometer has a first thermometer that measures the water temperature of the first pumping water source and a second thermometer that measures the water temperature of the second pumping water source,
A reactor water injection device, further comprising a water source selection device that enables use of any of the first and second pumping water sources. In the reactor water injection device according to any one of claims 1 to 8,
A reactor water injection apparatus, wherein the condensing water source and the pumping water source are integrated.   A nuclear power plant comprising the reactor water injection device according to any one of claims 1 to 10.

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