Test method for evaluating control rod insertability during earthquakes, and test facility for evaluating control rod insertability during earthquakes

Abstract

To provide an earthquake control rod insertability evaluation test method capable of easily realizing a control rod driving force with delay in a scram time equal to or greater than that of an actual BWR compared to the past.SOLUTION: An earthquake control rod insertability evaluation test method includes; a scram time acquisition step of obtaining a scram time and a control rod insertion speed in an earthquake resistance testing device; an insertion speed acquisition step of obtaining a scram time and a control rod insertion speed of a driving force simulation object of a control rod; a comparison step of comparing whether or not a difference between the scram time in the earthquake resistance testing device and the scram time of the driving force simulation object satisfies a stored threshold for a standard scram time in a nuclear reactor under operation, and comparing whether or not a difference between the control rod insertion speed of the earthquake resistance testing device and the control rod insertion speed of the driving force simulation object satisfies a stored threshold for a standard control rod insertion speed of the nuclear reactor under operation; and an adjustment step of adjusting the pressure of an accumulator of a hydraulic control unit and the volume of a gas container so as to satisfy the threshold, which is executed when it is determined that one of the two thresholds is not satisfied.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a test method and apparatus for evaluating the insertability of control rods in a boiling water nuclear reactor during an earthquake. [Background technology]

[0002] As an example of seismic testing equipment that can suppress the generation of seismic motion caused by vibration during testing, Patent Document 1 describes a test vessel in which mock fuel simulating fuel in a nuclear reactor and control rods are stored inside a container filled with water and a control rod drive mechanism is attached for inserting the control rod into the mock fuel, a reaction wall installed around the test vessel, a vibration exciter fixed to the reaction wall and vibrating the test vessel in the horizontal direction, and a load support mechanism and linear slide mechanism that support the test vessel so that the test vessel can move back and forth along the horizontal direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-8085 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a boiling water reactor, when a large earthquake occurs, control rods are inserted into the core to bring the reactor to an emergency shutdown. During an earthquake, the fuel assemblies arranged in the core vibrate in a bow shape and come into contact with the control rods, so there is a delay in inserting the control rods compared to when there is no earthquake.

[0005] An evaluation standard value is set for this control rod insertion time, and in seismic evaluation of control rod insertability, vibration tests are conducted using a test specimen with actual specifications for control rod insertability to confirm that the specific control rod insertion stroke arrival time (hereinafter referred to as scram time), which is determined for each type of boiling water reactor, is within the evaluation standard value.

[0006] Patent Document 1 discloses an example of an earthquake resistance test facility for evaluating scram time during an earthquake.

[0007] In the seismic test facility of Patent Document 1, since no equipment such as a pump for pressurizing the test vessel is provided, the test vessel is under atmospheric pressure. In contrast, in an actual reactor, the reactor core is subjected to reactor pressure. Therefore, the control rod driving force is adjusted without vibrating the fuel assemblies so that the scram time coincides with or is delayed from the value obtained under actual reactor conditions.

[0008] The control rod driving force is adjusted by the accumulator pressure of the hydraulic control unit and the capacity of the nitrogen gas container. However, when adjusting it to match or delay the scram time obtained under actual conditions, there are countless combinations of accumulator pressure and nitrogen gas container capacity, so it is expected that differences will arise in the dynamic characteristics of the control rod driving force.

[0009] In other words, in an excitation state in which the control rod is in contact with the fuel assembly, differences in the control rod driving force can cause differences in scram time even under the same excitation force conditions. Therefore, in order to further improve the reliability of seismic evaluation, a test method that is less likely to cause differences in control rod driving force is required.

[0010] The present invention provides a method and device for evaluating the insertability of control rods during an earthquake, which can more easily achieve a control rod driving force with a scram time delay equal to or greater than that of an actual boiling water reactor, as compared to the conventional method. [Means for solving the problem]

[0011] The present invention includes a plurality of means for solving the above-mentioned problems. One example of the present invention is a test method for evaluating the insertability of a control rod during an earthquake in a boiling water reactor, the test method comprising: a scram time acquisition step for acquiring a scram time and a control rod insertion speed in a seismic test apparatus; an insertion speed acquisition step for acquiring the scram time and the control rod insertion speed of a driving force simulation target of the control rod; a comparison step for comparing whether or not a difference between the scram time in the seismic test apparatus and the scram time of the driving force simulation target satisfies a threshold value related to a standard scram time in a stored operating reactor, and for comparing whether or not a difference between the control rod insertion speed of the seismic test apparatus and the control rod insertion speed of the driving force simulation target satisfies a threshold value related to a standard control rod insertion speed in a stored operating reactor; and an adjustment step that is executed when it is determined in the comparison step that either one of the threshold values ​​related to the standard scram time or the threshold value related to the standard control rod insertion speed is not satisfied, and that adjusts the pressure of an accumulator of a hydraulic control unit and the volume of a gas container so as to satisfy the threshold value.

[0012] As another example, a test method for evaluating control rod insertability during an earthquake for evaluating the insertability of a control rod in a boiling water reactor during an earthquake is characterized by comprising a control rod insertion stroke arrival time acquisition step for obtaining the control rod insertion stroke arrival time of two or more points in a seismic test device and the control rod insertion stroke arrival time at the same position as the two obtained points, a comparison step for comparing whether or not the difference between the control rod insertion stroke arrival time at the same control rod insertion stroke position of the seismic test device and that of a control rod driving force simulation target satisfies a threshold value related to the control rod insertion stroke arrival time in a stored operating reactor, and an adjustment step that is executed when it is determined in the comparison step that the threshold value is not satisfied, and that adjusts the pressure of the accumulator of the hydraulic control unit and the volume of the gas container so that the threshold value is satisfied. Effect of the Invention

[0013] According to the present invention, it is possible to easily realize a control rod driving force with a scram time delay equal to or greater than that of an actual boiling water reactor, as compared with the conventional art. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0014] [Figure 1] 1 is an overall schematic diagram of a test facility for evaluating the insertability of a control rod during an earthquake according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a functional block diagram illustrating a configuration of a treatment device in the test facility for evaluating control rod insertability during an earthquake according to the first embodiment. [Diagram 3] FIG. 2 is a diagram showing a test flow in the control rod insertion seismic test method according to the first embodiment. [Figure 4] FIG. 2 is a diagram showing an example of a display screen displayed on a display unit in the test facility for evaluating control rod insertability during an earthquake according to the first embodiment. [Diagram 5] FIG. 11 is a diagram showing another example of a display screen displayed on the display unit in the test facility for evaluating control rod insertability during an earthquake according to the first embodiment. [Figure 6] FIG. 11 is an overall schematic diagram of a test facility for evaluating the insertability of a control rod during an earthquake according to a second embodiment of the present invention. [Figure 7] FIG. 11 is a functional block diagram illustrating the configuration of a treatment device in the test facility for evaluating control rod insertability during an earthquake according to the second embodiment. [Figure 8] FIG. 13 is a diagram showing a test flow in the control rod insertion seismic test method according to the second embodiment. [Figure 9] FIG. 11 is a diagram showing an example of a display screen displayed on a display unit in the test facility for evaluating control rod insertability during an earthquake according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the control rod insertability evaluation test method and the control rod insertability evaluation test facility according to the present invention will be described with reference to the drawings. In the drawings used in this specification, the same or similar reference numerals are used to designate the same or corresponding components, and repeated description of these components may be omitted.

[0016] <Example 1> A first embodiment of the test method for evaluating the insertability of control rods during an earthquake and the test facility for evaluating the insertability of control rods during an earthquake according to the present invention will be described with reference to Figs. 1 to 5.

[0017] First, the overall configuration of the test facility for evaluating the insertability of control rods during an earthquake will be described with reference to Fig. 1. Fig. 1 is an overall schematic diagram of the test facility for evaluating the insertability of control rods during an earthquake according to the first embodiment.

[0018] The test facility 100 for evaluating control rod insertability during an earthquake shown in FIG. 1 is a facility for evaluating the control rod insertability during an earthquake of a boiling water reactor, and includes a seismic test device 101, a water pressure control unit 102, and a processing device 104.

[0019] Preferably, the earthquake control rod insertability evaluation test method of the present invention can be carried out using the earthquake control rod insertability evaluation test equipment 100 shown in FIG. 1 or the earthquake control rod insertability evaluation test equipment 100A of Example 2 described below, but is not limited thereto.

[0020] In this embodiment, the reactor for which the control rod insertability is to be evaluated is a boiling water reactor, but other types of reactors such as pressurized water reactors can also be used.

[0021] As shown in Figure 1, the seismic testing equipment 101 is equipped inside a test vessel 201 with mock fuel assemblies 202 simulating fuel assemblies in a nuclear reactor, control rods 203 to be inserted into the cross-sectional gaps between the mock fuel assemblies 202, fuel support brackets 204 supporting the lower end of the mock fuel assemblies 202, a mock core support plate 205 supporting the fuel support brackets 204, a mock upper lattice plate 206 supporting the upper end of the mock fuel assembly, and a control rod guide tube 207 at the lower end of the fuel support bracket 204 for storing the control rods 203 when not inserted.

[0022] The test vessel 201 is filled with a fluid 211 to simulate the environment of a nuclear reactor.

[0023] A control rod drive mechanism 208 for driving the control rod 203 is attached to the bottom of the test vessel 201, and a hydraulic control unit 102 for supplying the driving force to the control rod 203 is connected to the control rod drive mechanism 208 via scram piping 209.

[0024] The bottom end of the test vessel 201 is fixed to a vibration table 210 for vibrating the test vessel 201. Although Fig. 1 shows a case where one mechanism for vibrating the test vessel 201 is provided at the bottom end, it is not necessary to provide it at the bottom end, and one or more mechanisms can be provided at other positions, such as the vertical center or top end of the test vessel 201, or the center and top end.

[0025] The control rod drive mechanism 208 is equipped with a position detection probe 103 in which p (p is a natural number greater than or equal to 1) proximity sensors 212 are arranged so as to detect the position of the control rod 203, and when a control rod drive piston (omitted for convenience of illustration) connected to the lower end of the control rod 203 is in the vicinity of the proximity sensor 212, a signal is output to a processing device 104, thereby making it possible to measure the control rod insertion stroke arrival times ST1 to STp for each control rod insertion stroke.

[0026] The hydraulic control unit 102 is a drive source for the control rod 203 in the seismic test device 101 , and has at least an accumulator 216 and a nitrogen gas container 217 .

[0027] Next, the configuration of the treatment device 104 will be described with reference to Fig. 2. Fig. 2 is a functional block diagram for explaining the configuration of the treatment device in the test facility for evaluating control rod insertability during an earthquake according to the first embodiment.

[0028] The processing device 104 can be realized by a PC (PERSONAL COMPUTER) equipped with hardware such as a calculation device such as a CPU, a main storage device such as a semiconductor memory and an auxiliary storage device such as a hard disk, input devices such as a keyboard and a USB port, and an output device such as a display unit 215 consisting of a monitor, and the control of the operation of each device and various calculation processes described later are executed based on various programs.

[0029] The programs may be stored in an internal storage unit, an external recording medium, a data server (all not shown), etc., and may be read and executed by the CPU. The control processes may be integrated into one program, or may be separated into multiple programs, or may be a combination of these. Some or all of the programs may be realized by dedicated hardware, or may be modularized. Furthermore, the various programs may be installed from a program distribution server, an internal storage medium, or an external recording medium.

[0030] In this embodiment, the processing device 104 is composed of a storage unit 213 , a processing unit 214 , and a display unit 215 .

[0031] The memory unit 213 is a part that stores data Da1 such as information on the standard scram time and standard control rod insertion speed in an operating reactor that is the control rod driving force simulation target, obtained from the control rod driving force simulation target, and data Da2 consisting of control rod insertion stroke arrival times ST1 to STp and position information of the proximity sensor 212, obtained from the seismic testing equipment 101, and is composed of a main memory device such as the semiconductor memory described above and an auxiliary memory device such as a hard disk.

[0032] The processing unit 214 performs calculations based on the data stored in the memory unit 213 and compares the calculation results with a predefined threshold value, and in this embodiment is composed of a scrum time acquisition unit 214a, an insertion speed acquisition unit 214b, a comparison unit 214c, and an adjustment unit 214d.

[0033] The scram time acquisition unit 214a is a part that acquires the scram time and the control rod insertion speed in the seismic testing equipment 101, and is preferably the main body that executes the scram time acquisition step.

[0034] The insertion speed acquisition unit 214b is a part that acquires the scram time and the control rod insertion speed of the control rod 203 for which the driving force is to be simulated, and is preferably a main body that executes the insertion speed acquisition step.

[0035] The comparison unit 214c is a part that compares whether the difference between the scram time in the seismic testing equipment 101 and the scram time of the driving force simulation target satisfies the threshold value for the standard scram time stored in the memory unit 213, and also compares whether the difference between the control rod insertion speed of the seismic testing equipment 101 and the control rod insertion speed of the driving force simulation target satisfies the threshold value for the standard control rod insertion speed stored in the memory unit 213, and preferably is the main entity that executes the comparison step.

[0036] In this embodiment, the comparison unit 214c preferably compares whether the scram time of the seismic testing equipment 101 is equal to or longer than the scram time of the driving force simulation target, and whether the control rod insertion speed of the seismic testing equipment 101 is equal to or shorter than the control rod insertion speed of the driving force simulation target. The comparison unit 214c may compare whether the difference between the scram time of the seismic testing equipment 101 and the scram time of the driving force simulation target is within 0.1 seconds.

[0037] The adjustment unit 214d is a part that adjusts the pressure of the accumulator 216 of the hydraulic control unit 102 and the volume of the nitrogen gas container 217 so as to satisfy the threshold value when the comparison unit 214c determines that either the threshold value for the standard scram time or the threshold value for the standard control rod insertion speed has not been satisfied, and is preferably the main entity that executes the adjustment step.

[0038] The display unit 215 displays the data used in the calculations of the processing unit 214 and the results of judgment on the calculation results.

[0039] Next, the control rod insertion seismic test method according to this embodiment will be described with reference to FIGS.

[0040] First, the test flow in the first embodiment will be described with reference to Fig. 3. Fig. 3 is a diagram showing a test flow in the control rod insertion seismic test method in the first embodiment.

[0041] As shown in FIG. 3, first, the scram time acquisition unit 214a acquires a simulated scram time 301 and a simulated control rod insertion speed 302 for simulating the control rod driving force from a real boiling water reactor, a control rod insertion test simulating the temperature and pressure environment of the real reactor core, a numerical simulation, etc., and inputs these to the memory unit 213 of the processing device 104 (step S1, scram time acquisition step).

[0042] Next, the insertion speed acquisition unit 214b acquires the test facility scram time 303 and the test facility control rod insertion speed 304 in the seismic test equipment 101, and inputs them into the memory unit 213 of the processing device 104 (step S2, insertion speed acquisition step).

[0043] The test equipment scram time 303 and test equipment control rod insertion speed 304 in the seismic testing equipment 101 obtained in step S2 are data obtained when a control rod insertion test is previously performed using the seismic testing equipment 101 under non-vibration conditions at an arbitrary pressure of the accumulator 216 and volume of the nitrogen gas container 217.

[0044] The test facility scram time 303 and the test facility control rod insertion speed 304 in step S2 can be obtained, for example, by inputting the times ST1 to STp at which each control rod insertion stroke measured by the position detection probe 103 is reached into the storage unit 213 and calculating them in the insertion speed acquisition unit 214b. In this case, it is preferable that the test facility scram time 303 uses the time at which a specific control rod insertion stroke determined for each type of boiling water reactor is reached, and the test facility control rod insertion speed 304 uses the value obtained by performing a calculation in the processing unit 214 of dividing the interval between adjacent proximity sensors 212 by the difference in the time at which each control rod passes through the respective proximity sensors.

[0045] Next, the comparison unit 214c uses the simulated target scram time 301 input into the memory unit 213 in step S1 and the test equipment scram time 303 obtained in step S2 to determine whether the test equipment scram time 303 is greater than or equal to the simulated target scram time 301 (step S3, comparison step).

[0046] If the test facility scram time 303 is equal to or greater than the simulated target scram time 301, the test is judged as passed and the process proceeds to step S4. In contrast, otherwise, the test is judged as failed and the process proceeds to step S6.

[0047] Fig. 4 is a diagram showing an example of the display screen 218 displayed by the display unit 215. The display screen 218 in Fig. 4 displays the simulated scrum time 301, the test equipment scrum time 303, and the scrum time judgment result 321, so that the test personnel can grasp the judgment result at a glance.

[0048] Here, since the control rod driving force becomes smaller as the difference between the simulated target scram time 301 and the test facility scram time 303 becomes larger, it is desirable to keep the difference between the simulated target scram time 301 and the test facility scram time 303 within 0.1 seconds during testing.

[0049] Next, a judgment is made using the simulation target control rod insertion speed 302 inputted to the memory unit 213 in step S1 and the test facility control rod insertion speed 304 obtained in step S2.

[0050] Specifically, it is determined whether the test equipment control rod insertion speed 304A (see FIG. 5) in the control rod insertion stroke for evaluating the scram time matches the simulated target control rod insertion speed 302A (see FIG. 5) in the same control rod insertion stroke, or whether the test equipment control rod insertion speed 304A is greater (step S4, comparison step).

[0051] If the test facility control rod insertion speed 304A is equal to or lower than the simulation target control rod insertion speed 302A, the test is judged as passed and the process proceeds to step S5, whereas otherwise the test is judged as failed and the process proceeds to step S6.

[0052] Fig. 5 is a diagram showing an example of a display screen 218A displayed by the display unit 215. The display screen 218A in Fig. 5 displays a simulated control rod insertion speed 302, a test facility control rod insertion speed 304, a simulated control rod insertion speed 302A in the control rod insertion stroke for evaluating the scram time, a test facility control rod insertion speed 304A in the control rod insertion stroke for evaluating the scram time, and a judgment result 322 of the control rod insertion speed. This allows the tester to grasp the judgment result at a glance, similar to Fig. 4.

[0053] If the judgment result 321 of the scram time in step S3 and the judgment result 322 of the control rod insertion speed in step S4 are both passed, a control rod insertion test during vibration is carried out in the seismic test device 101 (step S5).

[0054] On the other hand, if it is determined to be unsuccessful in step S3 or step S4, the pressure in the accumulator 216 or the volume of the nitrogen gas container 217 is adjusted (step S6, adjustment step).

[0055] Thereafter, the test equipment scram time 303 and the test equipment control rod insertion speed 304 in the seismic testing equipment 101 for the values ​​adjusted in step S6 are obtained in step S2, and the adjustment process is repeated until steps S3 and S4 are passed and the test during vibration in step S5 can actually be performed.

[0056] In this way, the time history of the control rod insertion speed when not vibrating is convex upward and tends to decrease monotonically after the maximum value. In addition, since the integral value of the control rod driving force is proportional to the control rod speed, it is possible to specify a control rod driving force that is the same as or smaller than the simulated target by adjusting the pressure of the accumulator 216 and the volume of the nitrogen gas container 217 so that both the scram time judgment result 321 and the control rod insertion speed judgment result 322 pass.

[0057] In this embodiment, the scram time and the control rod insertion speed are used, but since the scram piping flow rate is correlated with the control rod insertion speed, a flow meter may be installed in the scram piping 209 of the seismic test device 101 and the scram piping flow rate may be used instead of the control rod insertion speed. Also, the control rod insertion speed may be calculated by differentiating the control rod insertion displacement or integrating the control rod insertion acceleration.

[0058] In addition, in steps S3 and S4, if there are multiple control rod insertion strokes for which the scram time is evaluated, the determinations in steps S3 and S4 are made for each of the control rod insertion strokes to be evaluated.

[0059] Next, the effects of this embodiment will be described.

[0060] According to the above-described first embodiment of the present invention, it is possible to identify a control rod driving force that is the same as or smaller than the simulated target, thereby reducing the possibility of differences in scram time compared to the conventional art and further improving the evaluation accuracy.

[0061] In addition, the comparison unit 214c compares whether the scram time of the seismic testing equipment 101 is equal to or greater than the scram time of the driving force simulation target, and whether the control rod insertion speed of the seismic testing equipment 101 is equal to or less than the control rod insertion speed of the driving force simulation target, thereby enabling further improvement in the accuracy of the evaluation test.

[0062] Furthermore, the comparison unit 214c can further improve the accuracy of the evaluation test by making a comparison to see whether the difference between the scram time of the earthquake resistance test device 101 and the scram time of the driving force simulation target is within 0.1 seconds.

[0063] <Example 2> Second Embodiment A test method for evaluating the insertability of a control rod during an earthquake and a test facility for evaluating the insertability of a control rod during an earthquake according to a second embodiment of the present invention will be described with reference to FIGS.

[0064] First, the configuration of the test facility for evaluating the insertability of control rods during an earthquake will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is an overall schematic diagram of the test facility for evaluating the insertability of control rods during an earthquake according to the second embodiment.

[0065] 6, a test facility 100A for evaluating control rod insertability during an earthquake according to this embodiment includes a seismic test device 101, a processing device 104A, and a water pressure control unit 102. Among these, the configurations and operations of the seismic test device 101 and the water pressure control unit 102 are the same as those in the first embodiment.

[0066] In contrast, the processing device 104A has a different configuration in that it uses two or more control rod insertion stroke arrival times to identify the control rod driving force.

[0067] Next, the configuration of the processing device 104A will be described with reference to Fig. 7. Fig. 7 is a functional block diagram for explaining the configuration of the processing device in the test facility for evaluating control rod insertability during an earthquake according to the second embodiment.

[0068] 7, the processing device 104A is preferably configured as a PC like the processing device 104, and the processing device 104A is configured from a storage unit 213A, a processing unit 214A, and a display unit 215. Among them, the processing unit 214A is configured from a control rod insertion stroke arrival time acquisition unit 214A1, a comparison unit 214A2, and an adjustment unit 214A3.

[0069] The storage unit 213A is a part that stores the control rod insertion stroke arrival time in an operating nuclear reactor, and has basically the same configuration as the storage unit 213.

[0070] The control rod insertion stroke arrival time acquisition unit 214A1 is a part that acquires the control rod insertion stroke arrival times of two or more points in the seismic testing equipment 101, and the control rod insertion stroke arrival time at the same position as the two acquired points, and preferably is the main entity that executes the control rod insertion stroke arrival time acquisition step.

[0071] The comparison unit 214A2 is a part that compares whether the difference in the control rod insertion stroke arrival time at the same control rod insertion stroke position between the seismic testing equipment 101 and the control rod driving force simulation target satisfies a threshold value for the control rod insertion stroke arrival time stored in the memory unit 213A, and preferably serves as the main body that executes the comparison step.

[0072] In this embodiment, it is preferable that the comparison unit 214A2 increases the threshold value for the control rod insertion stroke arrival time as the obtained point is farther away from the initial control rod insertion position. Also, it is preferable that the difference in the control rod insertion stroke arrival time is within 0.1 seconds.

[0073] The adjustment unit 214A3 has the same configuration as the adjustment unit 214d, and when the comparison unit 214A2 determines that the threshold value is not satisfied, adjusts the pressure of the accumulator 216 of the water pressure control unit 102 and the volume of the nitrogen gas container 217 so as to satisfy the threshold value, and preferably becomes the main body that executes the adjustment step.

[0074] Next, a control rod insertability seismic test method according to this embodiment will be described with reference to Fig. 8 and Fig. 9. Fig. 8 shows a test flow of the control rod insertability seismic test in this embodiment 2. Fig. 9 is a diagram showing an example of a display screen displayed on the display unit.

[0075] As shown in FIG. 9, first, in the control rod insertion stroke arrival time acquisition unit 214A1, a simulation target control rod insertion stroke arrival time SUn at an arbitrary control rod insertion stroke is obtained from a control rod driving force simulation target similar to that in the first embodiment (step SA1, control rod insertion stroke arrival time acquisition step).

[0076] Here, n is a natural number of 2 or more, and indicates the evaluation score of the control rod insertion stroke. The smaller the value of n, the closer the control rod insertion stroke is to the initial insertion position of the control rod 203. The simulated target control rod insertion stroke arrival time SUn includes the simulated target scram time 301. The obtained simulated target control rod insertion stroke arrival time SUn is input to the memory unit 213A of the processing device 104A.

[0077] Next, in the control rod insertion stroke arrival time acquisition unit 214A1, the test equipment control rod insertion stroke arrival time SVn at the same control rod insertion stroke evaluation point as in step SA1 is acquired and input into the memory unit 213 of the processing device 104 (step SA2, control rod insertion stroke arrival time acquisition step).

[0078] The test equipment control rod insertion stroke arrival time SVn at the same control rod insertion stroke evaluation point as step SA1 obtained in step SA2 is data obtained in advance when a control rod insertion test under non-vibration conditions is performed using the seismic testing equipment 101.

[0079] Next, in the comparison unit 214c, the difference DTn between the control rod insertion stroke arrival times at the same control rod insertion stroke evaluation point is calculated using the simulation target control rod insertion stroke arrival time SUn stored in the storage unit 213 in step SA1 and the test equipment control rod insertion stroke arrival time SVn stored in the storage unit 213 in step SA2. DTn is calculated according to the following formula (1) (step SA3, comparison step).

[0080]

number

[0081] Here, in equation (1), DTn is the difference in control rod insertion stroke arrival time at the nth test equipment control rod insertion stroke evaluation point, SVn is the test equipment control rod insertion stroke arrival time at the nth test equipment control rod insertion stroke evaluation point, and SUn is the simulated target control rod insertion stroke arrival time at the nth test equipment control rod insertion stroke evaluation point.

[0082] In addition, for the difference DTn in the control rod insertion stroke arrival time obtained by equation (1), the inequality shown in the following equation (2) is set as a threshold value.

[0083]

number

[0084] Then, it is determined whether or not this inequality holds (step SA3, comparison step). If it holds, it is determined to be passed and the process proceeds to step S5, otherwise it is determined to be failed and the process proceeds to step S6.

[0085] Steps S5 and S6 are the same as the processes shown in FIG. 5, and therefore the description thereof will be omitted.

[0086] Fig. 9 is a diagram showing an example of a display screen 218B displayed by the display unit 215 in Example 2. The display screen 218B in Fig. 9 displays the simulation target control rod insertion stroke arrival time SUn, the test equipment control rod insertion stroke arrival time SVn, the difference DTn between the control rod insertion stroke arrival times, and the judgment result 323 of the control rod insertion stroke arrival time, so that the tester can grasp the judgment result at a glance.

[0087] In addition, since the larger the difference in control rod insertion stroke arrival time DTn, the smaller the control rod driving force, it is desirable to keep DTn within 0.1 seconds during testing.

[0088] The other configurations and operations are substantially the same as those of the test method for evaluating control rod insertability during an earthquake and the test facility for evaluating control rod insertability during an earthquake described in the first embodiment, and therefore details are omitted.

[0089] The test method for evaluating control rod insertability during an earthquake and the test equipment for evaluating control rod insertability during an earthquake of Example 2 of the present invention can also provide effects substantially similar to those of the test method for evaluating control rod insertability during an earthquake and the test equipment for evaluating control rod insertability during an earthquake of Example 1 described above.

[0090] <Other> The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the configurations described. Also, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. Also, it is possible to add the configuration of another embodiment to the configuration of one embodiment. Also, it is possible to delete a part of the configuration of each embodiment, or to add or replace another configuration. [Explanation of symbols]

[0091] 100,100A…Earthquake control rod insertion evaluation test facility 101… Earthquake resistance testing equipment 102...Water pressure control unit 103...Position detection probe 104, 104A... Processing device 201...Test vessel 202…Simulated fuel assembly 203…Control rod 204…Fuel support bracket 205…Simulated core support plate 206…Mock upper lattice plate 207...Control rod guide tube 208...Control rod drive mechanism 209…Scram piping 210…Vibration table 211...Fluid 212…Proximity sensor 213,213A...Storage section 214, 214A... Processing section 214a…Scrum Time Acquisition Section 214b…insertion speed acquisition unit 214c…Comparison section 214d…adjustment section 214A1…Control rod insertion stroke arrival time acquisition section 214A2…Comparison section 214A3…Adjustment section 215...Display section 216…Accumulator 217...Nitrogen gas cylinder 218,218A,218B…Display screen 301…Simulated scrum time 302, 302A: Simulated control rod insertion speed 303…Test facility scrum time 304, 304A…Test facility control rod insertion speed 321,322,323…Judgment result

Claims

1. A test method for evaluating the insertability of a control rod during an earthquake in a boiling water reactor, comprising: a scram time acquisition step for acquiring the scram time and the control rod insertion speed in the seismic test device; an insertion speed acquisition step for acquiring a scram time and a control rod insertion speed of a control rod driving force simulation target; a comparison step of comparing whether or not a difference between the scram time in the seismic test apparatus and the scram time of the driving force simulation target satisfies a stored threshold value related to a standard scram time in an operating reactor, and comparing whether or not a difference between a control rod insertion speed of the seismic test apparatus and the control rod insertion speed of the driving force simulation target satisfies a stored threshold value related to a standard control rod insertion speed in an operating reactor; an adjustment step that is executed when it is determined in the comparison step that either one of the threshold value related to the standard scram time or the threshold value related to the standard control rod insertion speed is not satisfied, and that adjusts the pressure of the accumulator of the hydraulic control unit and the volume of the gas container so as to satisfy the threshold value. A test method for evaluating control rod insertability during an earthquake.

2. The method for evaluating control rod insertability during an earthquake according to claim 1, In the comparison step, a comparison is made as to whether or not the scram time of the seismic test device is equal to or longer than the scram time of the driving force simulation target, and whether or not the control rod insertion speed of the seismic test device is equal to or shorter than the control rod insertion speed of the driving force simulation target. A test method for evaluating control rod insertability during an earthquake.

3. The method for evaluating control rod insertability during an earthquake according to claim 2, In the comparison step, a comparison is made as to whether or not the difference between the scram time of the earthquake resistance test device and the scram time of the driving force simulation target is within 0.1 seconds. A test method for evaluating control rod insertability during an earthquake.

4. A test method for evaluating the insertability of a control rod during an earthquake in a boiling water reactor, comprising: a control rod insertion stroke arrival time acquisition step of acquiring the control rod insertion stroke arrival times at two or more points in the seismic test device and the control rod insertion stroke arrival times at the same positions as the two points acquired; a comparison step of comparing whether or not a difference between the control rod insertion stroke arrival time at the same control rod insertion stroke position of the seismic test device and the control rod driving force simulation target satisfies a stored threshold value related to the control rod insertion stroke arrival time in an operating nuclear reactor; an adjustment step, which is executed when it is determined in the comparison step that the threshold value is not satisfied, of adjusting the pressure of the accumulator of the water pressure control unit and the volume of the gas container so as to satisfy the threshold value. A test method for evaluating control rod insertability during an earthquake.

5. The method for evaluating control rod insertability during an earthquake according to claim 4, In the comparison step, the threshold value for the control rod insertion stroke arrival time is increased as the obtained point is farther away from the initial control rod insertion position. A test method for evaluating control rod insertability during an earthquake.

6. The method for evaluating control rod insertability during an earthquake according to claim 5, The difference in the control rod insertion stroke arrival time is within 0.1 seconds. A test method for evaluating control rod insertability during an earthquake.

7. A test facility for evaluating seismic control rod insertability of a boiling water reactor, comprising: Earthquake resistance testing equipment; A control device; a hydraulic control unit which is a drive source for a control rod in the seismic testing apparatus and has at least an accumulator and a gas container; The control device includes: A memory unit that stores standard scram times and standard control rod insertion rates for operating nuclear reactors; a scram time acquisition unit for acquiring a scram time and a control rod insertion speed in the seismic testing apparatus; an insertion speed acquisition unit for acquiring a scram time and a control rod insertion speed of a control rod driving force simulation target; a comparison unit which compares whether a difference between the scram time in the seismic testing apparatus and the scram time of the driving force simulation target satisfies a threshold value related to the standard scram time stored in the storage unit, and compares whether a difference between a control rod insertion speed of the seismic testing apparatus and a control rod insertion speed of the driving force simulation target satisfies a threshold value related to the standard control rod insertion speed stored in the storage unit; an adjustment unit that is executed when the comparison unit determines that either one of the threshold values ​​related to the standard scram time or the threshold value related to the standard control rod insertion speed is not satisfied, and adjusts the pressure of the accumulator of the water pressure control unit and the volume of the gas container so that the threshold value is satisfied. A test facility for evaluating the insertability of control rods during an earthquake.

8. The test facility for evaluating control rod insertion performance during an earthquake according to claim 7, The comparison unit compares whether a scram time of the seismic test device is equal to or longer than a scram time of the driving force simulation target, and whether a control rod insertion speed of the seismic test device is equal to or shorter than a control rod insertion speed of the driving force simulation target. A test facility for evaluating the insertability of control rods during an earthquake.

9. 9. The test facility for evaluating control rod insertion performance during an earthquake according to claim 8, The comparison unit compares whether a difference between the scram time of the earthquake resistance test device and the scram time of the driving force simulation target is within 0.1 seconds. A test facility for evaluating the insertability of control rods during an earthquake.

10. A test facility for evaluating seismic control rod insertability of a boiling water reactor, comprising: Earthquake resistance testing equipment; A control device; a hydraulic control unit which is a drive source for a control rod in the seismic testing apparatus and has at least an accumulator and a gas container; The control device includes: A memory unit that stores a control rod insertion stroke arrival time in an operating nuclear reactor; a control rod insertion stroke arrival time acquisition unit for acquiring the control rod insertion stroke arrival times of two or more points in the seismic testing apparatus and the control rod insertion stroke arrival times at the same positions as the two acquired points; a comparison unit that compares whether a difference between the control rod insertion stroke arrival times at the same control rod insertion stroke position of the seismic test device and a control rod driving force simulation target satisfies a threshold value related to the control rod insertion stroke arrival time stored in the storage unit; an adjustment unit that is executed when the comparison unit determines that the threshold value is not satisfied, and adjusts the pressure of the accumulator of the water pressure control unit and the volume of the gas container so that the threshold value is satisfied. A test facility for evaluating the insertability of control rods during an earthquake.

11. In the test facility for evaluating control rod insertion performance during an earthquake according to claim 10, The comparison unit increases the threshold value for the control rod insertion stroke arrival time as the obtained point is farther away from the initial control rod insertion position. A test facility for evaluating the insertability of control rods during an earthquake.

12. The test facility for evaluating control rod insertion performance during an earthquake according to claim 11, The difference in the control rod insertion stroke arrival time is within 0.1 seconds. A test facility for evaluating the insertability of control rods during an earthquake.

Images