JP2006145417A - Moving type in-reactor neutron measuring instrument, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein a long time is required for calibrating a neutron detector over the whole nuclear reactor, when securing positional precision of a TIP detector signal, by making slow a moving speed, in the reactor, of the TIP detector that is a detecting part of a moving type in-reactor neutron measuring instrument (TIP), and by reducing a moving distance of the TIP detector within a time difference between reading-in timing of a positional signal and reading-in timing of a detector signal. <P>SOLUTION: In this moving type in-reactor neutron measuring instrument for measuring a neutron beam distribution along an axial direction of the nuclear reactor, by inserting the TIP detector 6 into a plurality of guide tubes 5 installed inside a reactor core 2 and moving it, the moving of the TIP detector 6 is stopped during executing the reading-in of the positional signal 15a and the output signal 6a of the TIP detector in the guide tube 5, and the TIP detector 6 is moved quickly to a detector signal reading-in position planned in the next after finishing the execution of the reading-in for the positional signal and the output signal, as to control of a detector cable driving device 12 for winding/feeding a cable 7 attached with the TIP detector 6 in its tip. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mobile in-core instrumentation apparatus and method for calibrating a neutron flux detector permanently installed in a nuclear reactor.

  In a boiling water reactor, in order to measure the neutron flux in the reactor in the power operation state, a plurality of fixed fission ionization chamber type neutron detectors are installed in the radial direction and longitudinal direction of the core. When this neutron detector is irradiated with neutrons in a nuclear reactor, the fission material applied to the electrode undergoes fission, and the ionized material released at that time is measured as an electrical signal to measure the neutron flux. It is to be measured and is called a local output region monitoring device (hereinafter referred to as LPRM). An LPRM neutron flux detector is called an LPRM detector.

Since the amount of fission material applied to the electrodes of the neutron detector is consumed by neutron irradiation, the sensitivity of the neutron detector decreases with the operating time of the reactor.
For this reason, the LPRM detector in the reactor calibrates the sensitivity at regular intervals using a calibration neutron detector stored in a shielding vessel installed outside the reactor containment vessel during normal operation. I am doing so. A device used for this purpose is a mobile in-reactor neutron measurement device (hereinafter referred to as TIP), and a TIP detector is referred to as a TIP detector.

  In the nuclear reactor, a plurality of detector assemblies each including a plurality of LPRM detectors and a guide tube for passing a TIP detector attached to the tip of a cable are installed at equal intervals. The front end of each guide tube reaches the core top, and the rear end is provided so as to protrude out of the reactor containment vessel from the core bottom. The TIP detector is inserted into one guide tube selected by the indexing device among the guide tubes, and sent to the top of the reactor core. Thereafter, the cable is wound up, and when the TIP detector moves (scans) from the core top to the bottom, the neutron distribution in the core axis direction is measured. The position signal of the TIP detector and the output signal of the TIP detector are input to the XY recorder, and the TIP detector output signal for the position signal is recorded on the XY coordinate plane, and also input to the process computer. This is used for core distribution calculation and core performance calculation.

  The portion of the guide tube that protrudes outside the reactor containment vessel is connected to the index device, and the TIP detector is inserted into the only guide tube selected by the index device. One TIP detector is sequentially inserted into a plurality of guide tubes to perform sensitivity calibration of the LPRM detector of the entire reactor. (For example, refer to Patent Documents 1 and 2).

  In addition, there are multiple (for example, 3) TIP detectors in a nuclear power plant, and the neutron distribution after calibrating the relative sensitivity of all TIP detectors with a common guide tube that can be inserted into any TIP detector. We are trying to measure. Here, there is one drive unit for one TIP detector, and a plurality of detections are made on a common guide tube by a TIP control unit (TCU) in order to randomly insert three TIP detectors. Monitoring is performed so that the device is not inserted (see, for example, Patent Document 3).

On the other hand, in boiling water reactors, crossed control rods are evenly installed in the core, and local neutrons around the control rods during the extraction operation using the output signal of the LPRM detector described above. The rise of the bundle is monitored by a control rod pull-out monitoring monitor (BRM). Output signals of all LPRM detectors installed in the core are input to this control rod pull-out monitoring monitor.
JP 2000-28782 A Japanese Unexamined Patent Publication No. 2000-258586 Japanese Unexamined Patent Publication No. 01-250899

  In a conventional mobile in-reactor neutron measurement device (TIP), the drive control of the TIP detector and the measurement of the TIP detector signal are performed by separate devices, so the neutron flux at the position where the detector is scanning In order to measure correctly, it is necessary to synchronize the detector driving timing in the detector driving control device and the reading timing of the detector signal in the detector signal measuring device with high accuracy.

  For this reason, conventionally, the moving speed of the TIP detector in the reactor is slowed, and the TIP detector moves within the time difference between the timing of reading the position signal and the timing of reading the detector output signal. The position accuracy of the TIP detector signal was ensured by reducing the distance.

  However, slowing the TIP detector moving speed means that it takes a long time to calibrate the neutron detector for the entire reactor, and in particular, at the start-up of the reactor, Since the neutron detector is calibrated at each output stage, the time required for one calibration of the neutron detector has a great influence on the start-up time of the reactor.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a mobile in-reactor neutron measuring apparatus and method capable of shortening the calibration time of a neutron detector. .

  In order to achieve the above object, the invention of a mobile in-reactor neutron measuring apparatus according to claim 1 moves a mobile neutron flux detector inserted into a plurality of guide tubes installed in the reactor core. In the mobile neutron measurement apparatus for measuring the neutron flux distribution in the axial direction of the nuclear reactor, a detector at the tip is used to insert / extract the mobile neutron flux detector into / from the guide tube. And a detector position signal generator for detecting the position of the mobile neutron flux detector in the guide tube by detecting the winding / feeding amount of the detector cable. A detector cable driving device comprising: a detector position signal output from the detector position signal generator; and a detector output signal output from the mobile neutron flux detector; The movement of the mobile neutron flux detector is stopped when the reading of the signal is executed, and the motor is moved so that the mobile neutron flux detector is moved by a predetermined length after the reading execution of the detector output signal is completed. And a drive control / detector signal measuring device that outputs a drive command.

  According to the present invention, the movement of the mobile neutron flux detector is stopped when the detector output signal is read, and the mobile neutron flux detector is moved after the reading of the detector output signal is completed. Therefore, the movement of the mobile neutron flux detector does not occur between the time when the output signal of the mobile neutron flux detector is read and the time when the position signal is read, and the positional deviation of the mobile neutron flux detector signal does not occur.

  Embodiments of the mobile in-reactor neutron measurement apparatus according to the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the part which is common throughout an Example, and the overlapping description is abbreviate | omitted suitably.

Example 1
FIG. 1 is a system configuration diagram showing Embodiment 1 of a mobile in-reactor neutron measuring apparatus according to the present invention.
In FIG. 1, reference numeral 1 denotes a pressure vessel of a boiling water reactor, and a detector assembly 3 is installed in the core 2. Although only one detector assembly 3 is shown in FIG. 1, a plurality of detector assemblies 3 are actually installed at equal intervals. Moreover, the detector assembly 3 fixes LPRM detectors 4A, 4B, to 4D at four locations in the vertical direction, that is, from the core top to the core bottom, and is adjacent to the LPRM detectors 4A, 4B, to 4D. A guide tube 5 is provided. In this guide tube 5, a TIP detector 6 for detecting the in-core neutron flux is housed so as to be movable up and down, and this TIP detector 6 is a detector cable 7 having a built-in signal transmission line. And is housed movably between the top of the core, the bottom of the core, and a shielding vessel 11 provided outside the containment vessel 9 described later. Reference numeral 8 denotes an indexing device installed outside the pressure vessel 1. One of the plurality of guide tubes 5 is selected, and the TIP detection is detected at the tip of the selected guide tube 5. This is a device for inserting the detector cable 7 to which the device 6 is attached. This indexing device 8 sequentially inserts one TIP detector 6 into a plurality of guide tubes 5 so that the sensitivity calibration of the neutron detector in the entire reactor can be performed.

  The TIP detector 6 is pulled out from the guide tube 5 when the neutron flux is not measured, and is stored in the shielding container 11 through a valve assembly 10 provided outside the storage container 9. Although this valve assembly 10 is depicted as one block in the figure, it is actually composed of a valve for purging the gas in the guide tube 5, a cutting valve for cutting the tube in an emergency, and the like. It is closed when not measuring.

  Reference numeral 12 denotes a detector cable driving device (indicated as a TIP driving device in the figure) for winding or feeding the detector cable 7, and a cable take-up reel 13 for winding the detector cable 7 and not shown. A motor 14 that drives the cable take-up reel 13 via a clutch is built in, and the detector cable 7 is taken up or sent out depending on the rotation direction of the motor 14, and the TIP detector 6 in the guide tube 5 is taken up. It is configured to control the movement of.

  Further, in the detector cable driving device 12, a detector position signal generator 15 such as a synchro transmitter (SY) is attached to the cable take-up reel 13, and the cable take-up reel is detected by the detector position signal generator 15. 13 is configured to output a TIP detector position signal 15a based on the length of the detector cable 7 wound up.

  Further, the neutron flux in the core detected by the TIP detector 6 is configured to be output as a detector output signal 6a from a signal transmission line built in the detector cable 7 in the detector cable driving device 12. Yes.

  The detector output signal 6a and the detector position signal 15a output from the detector cable driving device 12 are supplied to a drive control / detector signal measuring device (drive control / monitor in the figure) installed in the central control room 17. The data is input to an XY recorder 19 through an apparatus 18 and the amount of neutron flux with respect to the position in the core axis direction is recorded on the XY plane. The detector output signal 6a and the detector position signal 15a are also input to the process computer 20 and used for calculation of distribution in the core and calculation of core performance.

FIG. 2 is a block diagram showing an example of the drive control / detector signal measuring apparatus 18 described above.
The drive control / detector signal measurement device 18 includes an input / output port 181, an I / O processing unit 182, a detector position processing unit 183, a detector output processing unit 184, and a drive control processing unit 185.

  Here, the detector position processing unit 183 performs arithmetic processing on data corresponding to the position signal based on the detector position signal 15a input through the input / output port 181. The detector output processing unit 184 passes through the input / output port 181. Data corresponding to the output signal is processed based on the input TIP detector output data 6a. The data processed by the detector position processing unit 183 and the detector output processing unit 184 are processed by the I / O processing unit 182 into signals that can be easily handled by external devices such as the XY recorder 19 and the process computer 20. After that, the data is input to the XY recorder 19 and the process computer 20 through the input / output port 181.

  FIG. 3 is a timing chart of various signals at the time of pulling out the TIP detector according to the first embodiment, and the horizontal axis is the time axis. In (a), a position signal representing position information from the core top of the TIP detector 6 to the core bottom and before the index device is taken on the vertical axis. The horizontal portion of the position signal represents the state in which the TIP detector 6 is not moving, and the downward sloping portion represents the state when the TIP detector is being pulled out (note that the sloping portion ascending to the right depicted on the left end of the figure). Represents the state when the TIP detector is delivered). (B) is a drive command to the motor 14 in the detector cable drive device 12 from the drive control monitor device 18 on the vertical axis, and represents the state when the TIP detector is inserted and withdrawn. In (c), the vertical axis indicates a signal that is turned on when the movement of the TIP detector 6 to a predetermined position (that is, a detector signal reading position) is completed and turned off during the movement. In (d), the vertical axis represents a signal that is turned on when the detector reading is executed (time; t).

  Note that T is the time for stopping the movement of the TIP detector 6 to measure the neutron flux and reading the signal, and expect a sufficient margin so that it can be read again when reading of the detector output fails. It is set to the time.

  As apparent from FIGS. 3A to 3D described above, the drive control processing unit 185 does not output a drive command to the motor 14 during the measurement and signal reading time (T) of the TIP detector 6. Then, the movement of the TIP detector 6 is stopped and the position thereof is held. During this measurement time (T), the TIP detector output 6a is read and the position signal 15a is read, and a predetermined measurement and signal reading time ( T) Immediately after the lapse of time, a TIP detector winding command is output to the motor 14, and the TIP detector 6 is moved at a high speed to the next scheduled detector signal reading position. Then, the neutron flux is measured at this position, and a new TIP detector output 6a and a position signal are input to the drive control / detector signal measuring device 18 to execute reading. Thereafter, the TIP detector 6 is sequentially moved at a high speed to a predetermined detector signal reading position to perform reading.

  As described above, the mobile reactor neutron measurement apparatus according to the first embodiment inputs the output signal 6a and the position signal 15a of the TIP detector 6 to one drive control / detector signal measurement apparatus 18. Since the motor 14 of the detection cable driving device 12 is driven and controlled in synchronization with the execution of reading the output signal 6a and the execution of reading the position signal 15a every predetermined time (T), the output signal 6a is read. There is no movement of the TIP detector 6 between the execution time and the reading execution time of the position signal 15a, and the positional deviation between the two signals does not occur.

  As a result, after the reading of the output signal and position signal is completed, the TIP detector 6 can be moved at a high speed from the current detector signal reading position to the next scheduled detector signal reading position. The calibration time of the LPRM detectors 4a to 4d can be greatly shortened as compared with the prior art.

(Example 2)
FIG. 4 is a system configuration diagram showing a second embodiment of the mobile in-reactor neutron measurement apparatus according to the present invention, and FIG. 5 is a block configuration diagram of the drive control / detector signal measurement apparatus 18 of the second embodiment. .
As shown in FIGS. 4 and 5, the second embodiment eliminates the XY recorder 19 in the first embodiment, and replaces the position signal of the TIP detector in the drive control / detector signal measuring device 18 instead. And a storage device 186 for storing the output signals at the positions in a one-to-one correspondence.

  In addition, after the extraction of the TIP detector 6 from the core 2 is completed, the data recorded in the table of the storage device 186 is collectively transmitted to the process computer 20, and peripheral devices (display device, recording device, etc.) of the process computer 20 are transmitted. ) 21 is used to display and record the relationship between the position signal 15a in the core axis direction and the TIP detection signal 6a corresponding to the position signal 15a. The other configuration is the same as the configuration of FIGS.

  In the first embodiment described above, the drive control / detector signal measuring device 18 needs to perform each process in synchronization with the pen movement speed of the XY recorder 19, so that the pulling speed of the TIP detector 6 is increased. However, in the case of the second embodiment, the drive control / detector signal measuring device 18 can perform each process at a high speed without being affected by the pen moving speed of the XY recorder 19. The drawing speed of the TIP detector 6 can be made faster than that in the first embodiment, and the calibration time of the neutron detector can be shortened accordingly.

(Example 3)
FIG. 6 is a system configuration diagram showing a third embodiment of a mobile in-reactor neutron measuring apparatus according to the present invention, and FIG. 7 is a block configuration diagram of a drive control / detector signal measuring apparatus 18 of the third embodiment. .
In the case of the neutron measuring apparatus in the mobile reactor described in the background art, the TIP detector 6 is pulled out at a continuous constant low speed, whereas in the above-described first and second embodiments, the TIP detector signal is read. At the time of execution, the movement of the TIP detector 6 is stopped, and after completion of reading, the TIP detector 6 is pulled out at a high speed, so that the TIP detector 6 intermittently and high-speeds the inner surface of the guide tube 5. Slide on. For this reason, there is a concern that the shavings accumulate at the TIP detector signal reading position inside the guide tube 5 while the measurement is repeated many times, and this shavings become an obstacle to the movement of the TIP detector 6.

  In the third embodiment, in view of this point, a torque sensor 16 is installed between the motor 14 of the detector cable driving device 12 and a clutch (not shown), and the torque required for winding (or sending) the cable. A value 16a is detected, and the detected torque value 16a is input to a detector position / torque sensor processing unit 187 newly provided in the drive control / detector signal measuring device 18 for monitoring. . Although a timing chart relating to the torque value 16a is not particularly shown, it is measured when the TIP detector 6 is pulled out (period of right downward in FIG. 9A), and within the next measurement / reading execution time (T). The signal is inputted into the drive control / detector signal measuring device 18 together with the output signal 6a and the position signal 15a and read.

  According to the third embodiment, the measured torque value is compared with a preset set value by comparing the torque value measured when the TIP detector 6 is pulled out (including when inserted) in some cases. If it becomes larger than that, it is judged that there is an abnormality in the guide tube 5 (clogging of shavings, deformation of the guide tube, etc.) and an alarm is output to alert the operator and the abnormal position to the detector position. By reading from the signal and displaying it on a display device such as a CRT or a liquid crystal (not shown), the abnormal portion of the guide tube 5 can be grasped.

  In general, the guide tube 5 is repeatedly removed and relaid every time the reactor is inspected. In the third embodiment, since the torque value can be automatically measured by the torque sensor during the trial run of the TIP detector after the guide pipe is laid, the exposure dose is greatly reduced as compared with the case where the operator measures with a torque wrench. can do.

  Note that the technique of measuring the torque value by installing a torque sensor in the detector cable drive device 12 has already been disclosed in JP 2002-71483 A, but the relationship between the torque value and the detector position signal Is not disclosed for the function of displaying and indicating an abnormal part of the guide tube 5.

Example 4
FIG. 8 is a system configuration diagram showing Embodiment 4 of the mobile in-reactor neutron measurement apparatus according to the present invention.
The mobile nuclear reactor neutron measurement apparatus of the fourth embodiment prepares a plurality of detector cable drive devices 12 (two in the figure, but can be applied to a number larger than two). The calibration time of the LPRM detector is further shortened by switching and driving the detection cable driving device 12 by one drive control / detector signal measuring device 18.
For this reason, the drive control / detector signal measurement device 18 according to the fourth embodiment is configured to newly provide a drive device selection unit 188.

  Although not specifically shown in FIG. 8, the normal mobile in-reactor neutron measurement apparatus includes a common guide tube in addition to the guide tube 5 described above as the guide tube 5 into which the TIP detector 6 is inserted. Therefore, in the fourth embodiment, it is assumed that individual TIP detectors 6 are inserted into the common guide tube and adjusted in advance so that the sensitivities of the TIP detectors 6 are substantially the same.

  After that, by selecting one of the plurality of detection cable drive devices 12 from one drive control / detector signal measuring device 18 and controlling the drive, the output signal 6a and the position are sequentially controlled in the same manner as in the previous embodiment. The signal 15a is read.

  In the case of the fourth embodiment, a plurality of TIP detectors 6 are inserted in advance into the core top position in the guide tube 5 before the start of TIP measurement, and a plurality of drive control / detector signal measuring devices 18 Since the detection cable driving device 12 is switched and sequentially driven and controlled, the TIP detector 6 is pulled out. Therefore, the TIP detector 6 is inserted / extracted for each channel as in the first to third embodiments. Compared with the case where the neutron flux is measured, the calibration time of the LPRM detector can be greatly shortened.

  Moreover, in order to stabilize the reactor output, it is necessary to ensure substantially the same output at the target position in the reactor. In the case of the fourth embodiment, a plurality of TIP detectors 6 are set in advance in the target position in the reactor. The neutron flux can be easily measured by insertion, and the relative calibration of the TIP detector 6 at the symmetrical position can be performed. If there is a difference of a predetermined value or more in the detected neutron flux value of the TIP detector 6 at the symmetrical position, it may be determined that the sensitivity of the detector is decreased, the reactor power is abnormal, etc. .

  In the fourth embodiment, when the relative sensitivity of a plurality of mobile neutron flux detectors is calibrated, a method for matching the center value of the measured neutron flux, a method for matching the average value of the measured neutron flux, or one Since there are various methods such as a method for adjusting to a mobile neutron flux detector with high sensitivity, a method considered to be optimal among these methods may be performed.

(Example 5)
FIG. 9 is a system configuration diagram showing Embodiment 5 of the mobile in-reactor neutron measurement apparatus according to the present invention.
In FIG. 9, the fifth embodiment is configured by adding an output region monitor to the second embodiment described above, 30 is an output region monitor, and 31 is a neutron flux from LPRM detectors 4A to 4D. A local output monitor 32, a control rod pull-out monitoring monitor 32, and a data transmission device 33.

  When the TIP detector 6 is pulled out, a timing signal 15a2 when the position of the TIP detector 6 reaches the core top, an arbitrary position between the core top and the core bottom (for example, the center of the core), or the bottom of the core, and guidance A selection signal (not shown) for the pipe 5 is transmitted to the control rod pull-out monitoring monitor 32 in the output area monitor 30. The control rod pull-out monitoring monitor 32 records the reactor average output and the outputs of the LPRM detectors 4A to 4D at each timing. Further, when the local output monitor 31 completes the extraction of the TIP detector 6 from the core, and the fluctuation range of the reactor average output and each LPRM detector signal is within a predetermined range during the extraction of the TIP detector at that time. It is determined that the neutron flux distribution measurement at the time of extraction is effective, and the determination result is output to the drive control / detector signal measurement device 18 and the process computer 20 via the data transmission device 33.

  In the case of the fifth embodiment, the monitoring function for the presence or absence of fluctuations in the reactor power during the extraction of the TIP detector, which was performed on the process computer 20 side in the first to fourth embodiments, can be eliminated. Hardware, that is, the TIP interface can be eliminated.

The system block diagram of Example 1 of the neutron measuring apparatus in a mobile reactor which concerns on this invention. 1 is a block configuration diagram of a drive control / detector signal measuring apparatus according to Embodiment 1. FIG. 3 is a timing chart when the TIP detector is pulled out in the first embodiment. The system block diagram of Example 2 of the mobile nuclear reactor neutron measuring apparatus which concerns on this invention. FIG. 6 is a block diagram of a drive control / detector signal measuring apparatus according to a second embodiment. The system block diagram of Example 3 of the mobile nuclear reactor neutron measuring apparatus which concerns on this invention. FIG. 6 is a block configuration diagram of a drive control / detector signal measuring apparatus according to a third embodiment. The system block diagram of Example 4 of the mobile nuclear reactor neutron measuring apparatus which concerns on this invention. The system block diagram of Example 5 of the mobile nuclear reactor neutron measuring apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Boiling water reactor pressure vessel, 2 ... Core, 3 ... Detector assembly, 4A, 4B, ~ 4D ... LPRM detector, 5 ... Guide tube, 6 ... TIP detector, 7 ... Detector cable, DESCRIPTION OF SYMBOLS 8 ... Indexing device, 9 ... Containment vessel, 10 ... Valve assembly, 11 ... Shielding container, 12 ... Detector cable drive device (TIP drive device), 13 ... Cable take-up reel, 14 ... Motor, 15 ... Detector position signal Generator (SY), 16 ... Torque sensor (τ), 17 ... Central control room, 18 ... Drive control / detector signal measuring device (drive control / monitor device), 181 ... I / O port, 182 ... I / O processing 183: Detector position processing unit, 184 ... Detector output processing unit, 185 ... Drive control processing unit, 186 ... Storage device, 187 ... Detector position / torque sensor processing unit, 188 ... Drive device selection unit, 19 ... XY recorder, 20 ... process computer, 21 ... peripheral device, 30 ... output area monitor, 31 ... local output monitor 32, control rod pull-out monitoring monitor, 33 ... data transmission device.

Claims (8)

Measurement of neutron flux in a mobile reactor by measuring the neutron flux distribution in the axial direction of the reactor by inserting and moving a mobile neutron flux detector in a plurality of guide tubes installed in the reactor core In the device
The position of the mobile neutron flux detector in the guide tube by detecting the winding / feeding amount of the detector cable and the motor that winds / feeds the detector cable with the mobile neutron flux detector attached to the tip A detector cable driving device having a detector position signal generator for detecting
The detector position signal output from the detector position signal generator and the detector output signal output from the mobile neutron flux detector are input and moved while the detector position signal and detector output signal are being read. The movement of the neutron flux detector is stopped, and after the execution of the reading of the detector position signal and the detector output signal, the mobile neutron flux detector is moved to the next predetermined detector signal reading position. And a drive control / detector signal measurement device for outputting a drive command to the motor.   A plurality of the detector cable drive devices are provided, and a drive device selection unit is provided in the drive control / detector signal measurement device, and the output of the drive control / detector signal measurement device is switched by the drive device selection unit. 2. The neutron measuring apparatus in a mobile reactor according to claim 1, wherein each of the detector cable driving devices can be individually controlled.   A plurality of the mobile neutron flux detectors are inserted into a target position in a nuclear reactor to measure neutron flux, and when there is a difference of a predetermined value or more between the measured values, it is determined that there is an abnormality and is notified. The neutron measuring apparatus for mobile reactors according to claim 2.   When pulling out the mobile neutron flux detector, the position of the mobile neutron flux detector reaches the core top, the bottom, and any position between the core top and the core bottom, and the timing signal of the guide tube The control rod pull-out monitoring monitor transmits a selection signal to the control rod pull-out monitoring monitor, and the control rod pull-out monitoring monitor at each timing incorporates a guide tube into which the reactor average output and the mobile neutron flux detector are inserted. The output of the fixed neutron detector installed in the reactor is recorded, and after the extraction of the mobile neutron flux detector from the core is completed, the average power of the reactor and each fixed output during the extraction of the mobile neutron flux detector at that time 2. The method according to claim 1, wherein when the fluctuation range of the neutron detector signal is within a predetermined range, it is determined that the neutron flux distribution measurement at the time of extraction is effective, and the determination result is output. Mobile reactor Neutron measurement device.   A torque sensor is installed between the motor and the clutch of the detector cable driving device, and the torque value is constantly measured when the mobile neutron flux detector is inserted / extracted. 2. An abnormal portion of the guide tube is specified by generating an alarm as an abnormality of the guide tube when the value exceeds the value, and reading and displaying the position from the detector position signal. The neutron measuring apparatus in the mobile reactor described.   The position of the mobile neutron flux detector and the output signal at that position are recorded in a storage device in a one-to-one relationship, and the extraction of the mobile neutron flux detector from the core is completed. The neutron measuring apparatus in a mobile nuclear reactor according to claim 1, wherein the neutron measuring apparatus in a mobile reactor is transmitted to a computer after being collected.   The computer inputs the mobile neutron flux detector position signal stored in the storage device and the mobile neutron flux detector output signal at that position, and causes the peripheral device to display or record the relationship between the two signals. The mobile in-reactor neutron measurement apparatus according to claim 6, Measurement of neutron flux in a mobile reactor by measuring the neutron flux distribution in the axial direction of the reactor by inserting and moving a mobile neutron flux detector in a plurality of guide tubes installed in the reactor core In the method
Concerning the control of the detector cable drive device that winds and sends out the cable with the mobile neutron flux detector attached to the tip, the position of the mobile neutron flux detector in the guide tube and the movement of the position signal during the execution of reading The detector cable stops the movement of the neutron flux detector and moves the mobile neutron flux detector to the next scheduled detector signal reading position after completing the reading of the position signal and output signal. A method for measuring neutrons in a mobile reactor, characterized by controlling a driving device.

Images