Abstract:
A reactor power output measurement device measuring a neutron flux with a traversing incore probe (TIP) traversing in a vertical direction in a core of a reactor, and calibrating a detection sensitivity of a local power range monitor based on a measured neutron flux distribution in the axial direction inside the reactor, which is provided with an integrated control device  9  for transmitting control data to all of TIP drive control devices  13   a  through  13   e  and performing control/monitor of all of detector drive systems  17   a  through  17   e . An integrated unit operation/monitor device  10  for operating/monitoring the integrated control device  9 , and a TIP integrated controller  8  comprising an integrated unit input/output device  11  for inputting detection signals obtained from TIP detectors  18   a  through  18   e  to the integrated control device  9  via the integrated unit input/output device  11 , and which switches to the integrated unit operation/monitor device  10  when the drive unit operation/monitor devices  15   a  through  15   e  suffer from failure.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a reactor power output measurement device, which measures a neutron flux inside a nuclear reactor with a traversing incore probe, and which calibrates the detection sensitivity of a local power range monitor based on the measured neutron flux level in the axial direction inside the nuclear reactor. 
     DESCRIPTION OF THE RELATED ART 
     Generally, an output detection of a boiling water reactor is performed by a local power range monitor (hereinafter referred to as LPRM). However, because the LPRM is permanently constructed inside the nuclear reactor, the detector sensitivity changes. Therefore, during plant start-up at starting or after a scheduled check, the neutron flux inside the nuclear reactor is measured using a traversing incore probe (hereinafter referred to as TIP), and the detector sensitivity of the LPRM is calibrated. 
     As an example of the prior art, a technique is disclosed in Japanese Patent Laid-open No. 2000-28782. The TIP detector is extracted from the nuclear reactor when not in use, and is inserted to a guide tube inside the nuclear reactor when in use, and measures the power output by moving in the vertical direction inside the reactor core. However, when a drive control device of a TIP drive controller which controls a TIP detector drive system for moving the TIP detector suffers from failure, it becomes impossible to move the TIP detector so that the TIP detector cannot be extracted to the position of a chamber shield. Therefore, the TIP drive control unit is provided with an extraction circuit by an interlock circuit, so that the TIP detector could be extracted to the interior of the chamber shield manually using the extraction circuit, even when the drive control device of the TIP drive controller stops. 
     Even when an operation/monitor device of the TIP drive controller suffers from failure, it becomes possible to operate the TIP detector drive system, so that the TIP detector is extracted to the interior of the chamber shield manually. 
     Also, a neutron flux signal and a positional signal obtained from the TIP detector is recorded by a XY recorder. 
     SUMMARY OF THE INVENTION 
     However, in the prior art, the shortening of the plant start-up time by efficiently performing a backup function for the operation/monitor device of the TIP detector drive system, and recording/storing the measured data, are not fully discussed. 
     The problem for the present invention is to perform efficiently the backup function for the operation/monitor device of the TIP detector drive system, and the recording/storing of the measured data. 
     In order to solve the above-mentioned problem, the present invention provides a detector drive system of a traversing incore probe (TIP) traversing in a vertical direction in an incore of a reactor; 
     a drive control unit including a drive unit operation/monitor means for operating and monitoring the TIP, and controlling the detector drive system; and 
     a TIP integrated control unit connected to the drive control unit and including an integrated unit operation/monitor means for operating and monitoring the TIP; 
     wherein operation is switched to the integrated unit operation/monitoring means when the drive unit operation/monitor means suffers from failure. 
     Also, the present invention provides an integrated unit operation/monitor means for operating and monitoring the TIP which is connected to the drive control unit including a drive unit operation/monitor means for operating and monitoring the TIP, and controlling the detector drive system; 
     an integrated unit input/output means for inputting/outputting a neutron flux measured by the TIP; 
     a TIP integrated control unit including an integrated control means for signal processing the measured neutron flux; 
     a data processing terminal and a printer connected to the TIP integrated control unit; and 
     a memory means for memorizing/storing the measured neutron flux; 
     wherein the measured neutron flux and the neutron flux distribution in the axial direction inside the reactor are memorized/stored, displayed and recorded using the device. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of the reactor power output measurement device according to an embodiment of the present invention; 
     FIG. 2 is a block diagram of the overall system of the present invention; 
     FIG. 3 is an explanatory view of the backup operation of the present invention; 
     FIG. 4 is an explanatory view of the memorizing/storing/recording of the measured neutron flux data according to the present invention; 
     FIG. 5 is a displayed screen of the integrated unit operation/monitor device according to the present invention; and 
     FIG. 6 is a captured screen of the data processing terminal of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The embodiment of the present invention will be described below with reference to the drawings. 
     FIG. 1 is a block diagram of the reactor power output measurement device according to an embodiment of the present invention. In FIG. 1, a reactor core  2  of a reactor  1  is installed with a plurality of LPRM detector assemblies  3  in a number corresponding to the reactor power output. For example, in a nuclear power plant of 1100 MWe class, forty-three LPRM detector assemblies  3  are provided. One LPRM detector assembly  3  contains LPRM detectors  5   a ,  5   b ,  5   c , and  5   d  and LPRM detectors  5   e ,  5   f ,  5   g , and  5   h , respectively. The LPRM detector assembly  3  is provided with guide tubes  4   a ,  4   b  for inserting the TIP detector  18   a . One TIP detector drive system  17   a  for driving the TIP detector  18   a  is installed for every ten LPRM detector assemblies. Therefore, in a nuclear power plant of 1100 MWe class, five TIP detector drive systems  17   a ,  17   b ,  17   c ,  17   d  and  17   e  are installed, as is shown in FIG.  2 . 
     A neutron flux measured by the TIP detector  18   a  is calculated at a TIP integrated controller  8 , and is input to a process computer  7 . Also, the neutron flux measured by the LPRM detector  5   a  of the LPRM detector assembly  3  is calculated at a LPRM  6 , and is input to a process computer  7 . The output of the TIP integrated controller  8  is input to a TIP drive controller  13   a . The output of the TIP drive controller  13   a  operates the TIP detector drive system  17   a , and drives the TIP detector  18   a.    
     FIG. 2 shows the structure of the overall system of the present embodiment. 
     The TIP detector drive system  17   a  is connected to a drive control device  14   a  via a signal cable and a drive unit input/output device  16   a , and is controlled by the control signal of the drive control device  14   a . A drive unit operation/monitor device  15   a  for operating/monitoring the drive control device  14   a , such as a flat display and the like, is connected to the drive control device  14   a . The drive control device  14   a , the drive unit operation/monitor device  15   a , and the drive unit input/output device  16   a  constitute the TIP drive controller  13   a . The same structure applies to other TIP drive controllers  13   b  through  13   e.    
     The TIP drive controllers  13   a  through  13   e  are connected to an integrated control device  9  via a transmission path  12  such as an optical transmission and the like. The integrated control device  9  transmits the control data to all of the TIP drive control devices  13   a  through  13   e , and controls and monitors all of the detector drive system. An integrated unit operation/monitor device  10 , such as a flat display and the like, is connected to the integrated control device  9 , and operates/monitors the integrated control device  9 . The detector signal obtained from the TIP detector  18   a  is input to the integrated control device  9  via a signal cable and an integrated unit input/output device  11 . The signals obtained from the TIP detectors  18   b  through  18   e  are also input to the integrated control device  9  via the integrated unit input/output device  11 . The integrated control device  9 , the integrated unit operation/monitor device  10 , the integrated unit input/output device  11  constitute a TIP integrated controller  8 . 
     The backup operation of the present embodiment will be described below with reference to FIG.  3 . In FIG. 3, the drive control device  14   a  is equipped with an operation/monitor device switching circuit  23  and a logic circuit  24 , and the TIP detector drive system  17   a  is equipped with an interlock circuit  19  including an operation-switching switch  21  and an operation-authorizing switch  22 , and a detector drive system driver  20 . 
     When conducting inserting/extracting operation of the TIP detector with the drive unit operation/monitor device  15   a  of the TIP controller  13   a , the inserting/extracting command output from the drive unit operation/monitor device  15   a  is input to the drive control device  14   a . Under the normal condition, the operation/monitor device switching circuit  23  is input with the signal from the drive unit operation/monitor device  15   a  side. When the AND condition is established by the logic circuit  24  from the inserting/extracting command and the operation-authorizing switch  22  provided to the interlock circuit  19 , the inserting/extracting command is input to the TIP detector drive system  17   a  through the drive unit input/output device  16   a . The inserting/extracting command input to the TIP detector drive system  17   a  is input to the detector drive system driver  20  via the interlock inside the interlock circuit  19 , and carries out inserting/extracting operation of the TIP detector  18   a.    
     When only the drive unit operation/monitor system  15   a  of the TIP drive controller  13   a  suffers from failure, the driving of the TIP is continued with the process mentioned hereinbelow, to backup the same. It is detected by the self-diagnosis function whether the device has failed or not. Also, the integrated unit operation/monitor device  10  displays the same screen as the drive unit operation/monitor device  15   a  under the normal condition. 
     When the failure of the drive unit operation/monitor device  15   a  is detected with the self-diagnosis function, the operator operates the operation-switching switch  21  provided to the interlock circuit  19 . With such operation, the operation/monitor device switching circuit  23  switches from the drive unit operation/monitor device  15   a  side to the TIP integrated controller  8  side. At the same time, the inserting/extracting operation command is output from the integrated unit operation/monitor device  10 . The inserting/extracting operation command output from the integrated unit operation/monitor device  10  is input to the drive control device  14   a  via the integrated control device  9  and the transmission path  12 , and is input to the TIP detector drive system  17   a  via the drive unit input/output device  16   a  when the AND condition is established by the logic circuit with the operation-authorizing switch  22 , as is in the case where the command is output from the drive unit operation/monitor device  15   a  under the normal condition. Next, the command is input to the detector drive system driver  20  via the interlock inside the interlock circuit  19 , and the detector drive system driver  20  carries out the extracting operation of the TIP detector  18   a.    
     As is mentioned above, when the drive unit operation/monitor device  15   a  suffers from failure, the present embodiment continues the TIP drive with the backup by the TIP integrated controller  8 , as well as prevents operational error by outputting the TIP operation command output from the TIP integrated controller  8  under the condition of the operation-authorization. 
     Next, the memorizing/storing/recording of the neutron flux data measured by the present embodiment will be described with reference to FIG.  4 . In FIG. 4, the integrated control device  9  is equipped with a processor  31 , a memory  32 , an operation/monitor device arithmetic unit  33 , and a communication arithmetic unit  34 , and is also provided with a printer  36  connected to the integrated unit operation/monitor device  10 , a data processing terminal  35  such as a personal computer and the like connected to the communication arithmetic unit  34  via a communication cable, and a printer  36  connected to the data processing terminal  35 . 
     The neutron flux data detected by the TIP detectors  18   a  through  18   e  is input to the integrated control device  9  via the integrated unit input/output device  11  of the TIP integrated controller  8 . The input neutron flux data is calculated at the processor  31 , converted to a screen display signal at the operation/monitor device arithmetic unit  33 , and is displayed at the screen of the integrated unit operation/monitor device  10 . At this point, the data may be recorded by the printer  36  with the printout operation by the operator. Also, the neutron flux data calculated by the processor  31  is input to the memory  32  and is memorized therein. When a download commencement command is output from the integrated unit operation/monitor device  10 , the download commencement command is input to the processor  31  via the operation/monitor device arithmetic unit  33 . The neutron flux data memorized in the memory  32  is read out from the memory  32  by the processor  31 , and is converted to a communication data by the communication arithmetic unit  34 . The neutron flux data converted to the communication data is input to the data processing terminal  35  via the communication cable. At the data processing terminal  35 , the neutron flux data is memorized/stored as an application data operating on the data processing terminal  35 . 
     The stored neutron flux data could be indicated on the data processing terminal  35  as is in the case with the integrated unit operation/monitor device  10 . Also, the neutron flux data stored in the data processing terminal  35  could be recorded by the printer  36  with the printout operation by the operator. 
     FIG. 5 indicates the display screen of the integrated unit operation/monitor device according to the present embodiment. 
     At the integrated unit operation/monitor device  10 , the neutron flux distribution in the axial direction inside the nuclear reactor is displayed, with the positional data of the axis within the nuclear reactor taken as the x-axis, and the measured neutron flux data taken as they-axis. In the figure, CH.  18   a  represents the TIP detector  18   a , No. 10 represents the LPRM No. 10, and  32 - 33  represents the position of the LPRM No. 10 inside the nuclear reactor. 
     By operating the printout of the displayed screen, the neutron flux distribution in the axial direction inside the nuclear reactor is recorded by the printer  36 . Also, by operating the download commencement, the download commencement command is input to the processor  31  via the operation/monitor device arithmetic unit  33 . The measured neutron flux data is read out from the memory  32  by the processor  31 , is converted to the communication data by the communication arithmetic unit  34 , and is input to the data processing terminal  35  via the communication cable. 
     FIG. 6 indicates the captured screen of the data processing terminal according to the present embodiment. 
     At the data processing terminal  35 , the neutron flux distribution in the axial direction inside the nuclear reactor is displayed as is in the case with the integrated unit operation/monitor device  10 , with the positional data of the axis within the nuclear reactor taken as the x-axis, and the measured neutron flux data taken as the y-axis. 
     The measured neutron flux data is transmitted from the integrated controller  8  to the drive controller  13   a  via the transmission path  12 . 
     As is explained above, according to the present invention, the operating/monitoring of the TIP with the operation/monitor device of the TIP integrated control device in a detector drive system of the traveling neutron flux detector could be continued, even when the operation/monitor device of the TIP drive controller suffers from failure. Therefore, the elongation of the plant start-up time could be prevented. 
     Also, with the processing by the TIP integrated controller according to the present invention, the measured neutron flux data could be memorized/stored/recorded efficiently, so that the accuracy of the reactor core performance calculation and the accuracy of the calibration of the LPRM detector could be enhanced.