| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 376254000 | Flux monitoring | 50 |
| 20080219394 | METHOD AND SYSTEM FOR CALCULATING AN ADJUSTED PEAK NODAL POWER IN A NUCLEAR REACTOR - Systems and methods for a nuclear reactor that include developing a first peaking factor at a first burnup threshold for one or more fuel rods. A second peaking factor is developed at a second burnup threshold for the fuel rods. The second burnup threshold is greater than the first burnup threshold. A third peaking factor is developed and is associated with a peak average power threshold for the fuel rods. An adjusted peak nodal power is generated for the fuel rods as a function of a base peak nodal power, the first peaking factor, the second peaking factor, and the third peaking factor. | 09-11-2008 |
| 20090052605 | HANDLING SYSTEM FOR IN-CORE DETECTOR THIMBLE TUBE OF REACTOR - A handling system for an in-core detector thimble tube of a reactor is disclosed. The handling system serves to withdraw and retract a thimble tube so as to provide a movement path of a movable detector used to measure a neutron flux within a reactor. For this, the handling system basically includes a thimble tube withdrawing/retracting device, which grips the thimble tube using a plurality of synthetic resin pinch rollers to withdraw and retract the thimble tube without any damage to the thimble tube, a thimble tube tensioning device, which applies a constant tensile force to the thimble tube to prevent the thimble tube from shaking or bending upon withdrawing/retracting operations, and a thimble tube platform, which temporarily keeps the withdrawn thimble tube at a fixed position without a risk of shaking of the thimble tube and provides a movement path of the thimble tube tensioning device. With automatic withdrawal/retraction of the thimble tube without damage provides advantages of an extended thimble tube exchange interval, improved safety of system facilities, reduced labor costs and working time, and reduced worker radiation exposure, shortened precaution/maintenance period, and enhanced reactor use efficiency. | 02-26-2009 |
| 20090154633 | Tranverse in-core probe monitoring and calibration device for nuclear power plants, and method thereof - A method and apparatus for the calibration of neutron flux monitoring devices used in a nuclear reactor core. The apparatus includes a transverse in-core probe (TIP) cable with a neutron absorber located a fixed distance apart from a TIP detector. The neutron absorber may be passed within close proximity of the neutron flux monitoring device such that a perceived drop in measured neutron flux occurs, whereupon the cable may be repositioned relative to the monitoring device to ensure that the TIP detector is within close proximity of the monitoring device for purposes of calibrating the monitoring device. | 06-18-2009 |
| 20090168946 | Thermal limit analysis with hot-channel model for boiling water reactors - An analytical method for the initial flux and transient hot water flow parameters for a boiling water reactor with single fuel bundle. Firstly, the method is to calculate intial flux and transient hot water flow parameter based on single fuel bundle. Then, it uses supplier provided CPR (Critical Power Ratio) correlation to calculate transient CPR and calculate the whole reactor core for hot water parameters as boundary condition. Iteration is used to figure out DCPR (Delta Critical Power Ratio). The obtained limit transient is selected as the maximum from DCPR. The maximum transient DCPR combines Safety Limit Minimum Critical Power Ratio (SLMCPR) and safety margin to figure out the OLMCPR (Operating Limit Minimum Critical Power Ratio). Both the plant layout and operational thermal limit are based on OLMCPR to assure the safety of reactor core. | 07-02-2009 |
| 20100128832 | DOPPLER REACTIVITY COEFFICIENT MEASURING METHOD - The output of a nuclear reactor is increased by a predetermined magnitude, and the neutron beam is measured as time-series data. The temperature of the moderator in the reactor is acquired as time-series data. Time-series data on the reactivity is acquired from the time-series data on the neutron beam by the reverse dynamic characteristic method with respect to a one-point reactor kinetics equation. Time-series data on the fuel temperature of a predetermined average acquired by using the time-series data on the reactor output and a predetermined dynamic characteristic model is acquired. The reactivity feedback contribution component is determined by using the time-series data on the reactivity and the applied reactivity. The Doppler reactivity coefficient is determined by using the time-series data on the average temperature of the moderator in the reactor, the time-series data on the fuel temperature of the predetermined average, the isothermal temperature reactivity coefficient, and the reactivity feedback contribution component. | 05-27-2010 |
| 20100150295 | SUBCRITICAL REACTIVITY MEASUREMENT METHOD - A method of determining the spatially corrected inverse count ratio (SCICR) used to determine reactor criticality, which subtracts a background noise signal from the source range detector output. The method monitors the source range detector signal at two different core temperature levels during a transient portion of the detector output as the power output of the reactor is increased in the source range. This information is employed to analytically determine the background noise signal, which is then subtracted from the detector outputs to obtain the SCICR reactivity measurement. | 06-17-2010 |
| 20100215138 | Fission Meter and Neutron Detection Using Poisson Distribution Comparison - A neutron detector system and method for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. Comparison of the observed neutron count distribution with a Poisson distribution is performed to distinguish fissile material from non-fissile material. | 08-26-2010 |
| 20100254504 | Power Monitoring System - The power monitoring system has: a local power range monitor (LPRM) unit that has a plurality of local power channels to obtain local neutron distribution in a nuclear reactor core; an averaged power range monitor (APRM) unit that receives power output signals from the LPRM unit and obtains average output power signal of the reactor core as a whole; and an oscillation power range monitor (OPRM) unit that receives the power output signals from the LPRM unit and monitors power oscillations of the reactor core. The output signals from the LPRM unit to the APRM unit and the output signals from the LPRM unit to the OPRM unit are independent. | 10-07-2010 |
| 20100266092 | COUNT RATE MEASUREMENT DEVICE AND ASSOCIATED FISSION CHAMBER CALIBRATION DEVICE - A fission chamber count rate measurement device and to the associated fission chamber calibration device; the count rate measurement device comprises: (1) a measurement cell, which contains the fission chamber (CH); (2) a neutron generator, which emits neutrons in the form of periodic pulses towards the fission chamber; (3) a neutron counter (K), which detects and counts the neutrons emitted by the neutron generator; and (4) a computing circuit, which delivers, over a predetermined time interval, a fission chamber count rate normalized with reference to the number of neutrons counted by the neutron counter (K). | 10-21-2010 |
| 20110002432 | INCORE INSTRUMENT CORE PERFORMANCE VERIFICATION METHOD - A subcritical physics testing program which utilizes vanadium self-powered incore instrumentation thimble assemblies to provide an actual measured powered distribution that is used to confirm that the core will operate as designed. The signals received from the incore detector elements are integrated until a fractional uncertainty is less than a specified level. The measured power distribution is then compared against a predicted power distribution for a given rod position or temperature difference. If the measured power distribution is within a specified tolerance to the predicted power distribution, then the core is expected to behave as predicted. | 01-06-2011 |
| 20110026661 | DETECTING PIN DIVERSION FROM PRESSURIZED WATER REACTORS SPENT FUEL ASSEMBLIES - Detecting diversion of spent fuel from Pressurized Water Reactors (PWR) by determining possible diversion including the steps of providing a detector cluster containing gamma ray and neutron detectors, inserting the detector cluster containing the gamma ray and neutron detectors into the spent fuel assembly through the guide tube holes in the spent fuel assembly, measuring gamma ray and neutron radiation responses of the gamma ray and neutron detectors in the guide tube holes, processing the gamma ray and neutron radiation responses at the guide tube locations by normalizing them to the maximum value among each set of responses and taking the ratio of the gamma ray and neutron responses at the guide tube locations and normalizing the ratios to the maximum value among them and producing three signatures, gamma, neutron, and gamma-neutron ratio, based on these normalized values, and producing an output that consists of these signatures that can indicate possible diversion of the pins from the spent fuel assembly. | 02-03-2011 |
| 20110044422 | Computer Implemented Method for Modelizing a Nuclear Reactor Core and a Corresponding Computer Program Product - A computer implemented method for modelizing a nuclear reactor core, including the steps of: partitioning the core in cubes to constitute nodes of a grid for computer implemented calculation, calculating neutron flux by using an iterative solving procedure of at least one eigensystem, the components of an iterant of the eigensystem corresponding either to a neutron flux, to a neutron outcurrent or to a neutron incurrent, for a respective cube to be calculated. | 02-24-2011 |
| 20110064181 | NEUTRON MONITORING SYSTEMS INCLUDING GAMMA THERMOMETERS AND METHODS OF CALIBRATING NUCLEAR INSTRUMENTS USING GAMMA THERMOMETERS - A method of calibrating a nuclear instrument using a gamma thermometer may include: measuring, in the instrument, local neutron flux; generating, from the instrument, a first signal proportional to the neutron flux; measuring, in the gamma thermometer, local gamma flux; generating, from the gamma thermometer, a second signal proportional to the gamma flux; compensating the second signal; and calibrating a gain of the instrument based on the compensated second signal. Compensating the second signal may include: calculating selected yield fractions for specific groups of delayed gamma sources; calculating time constants for the specific groups; calculating a third signal that corresponds to delayed local gamma flux based on the selected yield fractions and time constants; and calculating the compensated second signal by subtracting the third signal from the second signal. The specific groups may have decay time constants greater than 5×10 | 03-17-2011 |
| 20110110483 | Methods and systems for migrating fuel assemblies in a nuclear fission reactor - Illustrative embodiments provide methods and systems for migrating fuel assemblies in a nuclear fission reactor, methods of operating a nuclear fission traveling wave reactor, methods of controlling a nuclear fission traveling wave reactor, systems for controlling a nuclear fission traveling wave reactor, computer software program products for controlling a nuclear fission traveling wave reactor, and nuclear fission traveling wave reactors with systems for migrating fuel assemblies. | 05-12-2011 |
| 20110116589 | WATER BASED DISPERSIONS OF BORON OR BORON COMPOUNDS FOR USE IN COATING BORON LINED NEUTRON DETECTORS - A method for providing a boron-lined neutron detector. The method includes providing a boron-containing material and providing water. The method includes mixing the boron-containing material into the water to create a water-based liquid mixture and providing a substrate of a cathode of the neutron detector. The method includes applying the water-based liquid mixture to the substrate of the cathode and removing water from the water-based liquid applied to the substrate to leave a boron-containing layer upon the substrate that is sensitive to neutron impingement. The step of providing a boron-containing material may be to provide the material to include B-10. | 05-19-2011 |
| 20110268239 | METHOD OF CALIBRATING EXCORE DETECTORS IN A NUCLEAR REACTOR - A method of calibrating excore detectors for a pressurized water reactor (PWR) includes: measuring peripheral core flux signals using excore detectors disposed at a plurality of locations spaced about the periphery of the core, and using the measured power distribution from either a core monitoring system or in-core flux measurement. Calibration of the excore detectors is broken into two parts: (1) the relation between the excore detector signal and weighted peripheral assembly axial offset, and (2) the relation between weighted peripheral assembly axial offset and core average axial offset. Relation (2) can be determined by a representative neutronics model. Accuracy of the neutronics solution is improved by applying nodal calibration factors, which represent the ratio of the measured three-dimensional power distribution to the nodal predicted three-dimensional power distribution and correct the neutronic results to match what would be measured if predictive scenarios were actually performed in the actual reactor core. | 11-03-2011 |
| 20110286566 | NUCLEAR REACTOR OSCILLATION POWER RANGE MONITOR, AND METHOD AND PROGRAM THEREFOR - According to one embodiment, reactor oscillation power ranges monitor includes: a receiving unit which receives LPRM signals; an exclusion processing unit which searches the LPRM signals allocated to the cell for an LPRM signal corresponding to an exceptional condition; an averaging unit which averages the allocated LPRM signals; a time averaging unit which calculates a time average of the average flux value; a normalized value calculation unit which divides the average flux value by the time averaged flux value; an initialization unit which outputs an initialization signal identifying the cell allocated to an LPRM signal which is changed to correspond or not correspond to the exceptional condition; and a determination unit which derives at least one of amplitude and cycle of a power oscillation from the normalized value. | 11-24-2011 |
| 20110293058 | METHOD FOR MEASURING THE NEUTRON FLUX IN THE CORE OF A NUCLEAR REACTOR USING A COBALT DETECTOR AND ASSOCIATED DEVICE - A method for measuring the neutron flux in the core of a nuclear reactor, the method including several steps recurrently performed at instants separated by a period, the method comprising at each given instant the following steps: acquiring a total signal by a cobalt neutron detector placed inside the core of the reactor; assessing a calibration factor representative of the delayed component of the total signal due to the presence of cobalt 60 in the neutron detector; assessing a corrected signal representative of the neutron flux at the detector from the total signal and from the calibration factor; assessing a slope representative of the time-dependent change of the calibration factor between the preceding instant and the given instant; the calibration factor at the given instant being assessed as a function of the calibration factor assessed at the preceding instant, of the slope, and of the time period separating the given instant from the preceding instant. | 12-01-2011 |
| 20120057667 | RESONANCE CALCULATION PROGRAM AND ANALYZING APPARATUS - [Solving Means] A resonance calculation program is configured to calculate an effective cross section including Step S | 03-08-2012 |
| 20120177166 | WIRELESS IN-CORE NEUTRON MONITOR - An in-core neutron monitor that employs vacuum microelectronic devices to configure an in-core instrument thimble assembly that monitors and wirelessly transmits a number of reactor parameters directly from the core of a nuclear reactor without the use of external cabling. The in-core instrument thimble assembly is substantially wholly contained within an instrument guide tube within a nuclear fuel assembly. | 07-12-2012 |
| 20120201339 | EX-CORE NUCLEAR INSTRUMENTATION SYSTEM - An ex-core nuclear instrumentation system in which the width of measurable neutron detector current can be accurately widened is obtained. In order to output the condition of neutron flux in operation by performing arithmetic processing of a current value measured by a neutron detector by using a detector signal processing circuit, the detector signal processing circuit includes a current/voltage conversion unit which converts the current value converted by the neutron detector into a voltage value corresponding to the current value; and a variable gain amplification unit which has an operational amplifier having a resistance circuit for corresponding to current levels, the resistance circuit being capable of selecting a gain, and a D/A converter that adjusts the gain, and amplifies the voltage value converted by the current/voltage conversion unit. | 08-09-2012 |
| 20120257706 | REACTOR VESSEL INTERNALS RADIATION ANALYSES - The present invention relates to a computational system and method to analyze a radiation field in a light water nuclear reactor. The system and method include a radiation transport module for performing a neutron and gamma transport calculation of a reactor geometry model of the light water nuclear reactor for at least one fuel cycle; a material analysis module for analyzing flux data calculated by the radiation transport module for materials and/or components within the light water nuclear reactor; and a mobile component tracking module for calculating radiation exposure for components within the light water nuclear reactor which have more than one different location during or between the at least one fuel cycle. | 10-11-2012 |
| 20130010912 | Neutron Monitoring Systems Including Gamma Thermometers And Methods Of Calibrating Nuclear Instruments Using Gamma Thermometers - A neutron monitoring system uses a gamma thermometer to calibrate a nuclear instrument to ensure more accurate neutron flux measurements in a nuclear reactor core. The nuclear instrument generates a first signal proportional to a measured local neutron flux. The gamma thermometer generates a second signal proportional to a measured local gamma flux. A processor is used to compensate the second signal by filtering groups of delayed gamma sources to a reduced number of specific groups of delayed gamma sources. A third signal is calculated based upon yield fractions and time constants that are determined for the specific groups of delayed gamma sources. A gain of the nuclear instrument is calibrated based on a compensated second signal that is determined by subtracting the third signal from the second signal. | 01-10-2013 |
| 20130243146 | EX-CORE NUCLEAR INSTRUMENTATION SYSTEM - The ex-core nuclear instrumentation system includes a key hole, and it is configured such that in the state where a key lock switch is inserted into the key hole, writing to a electrically rewritable nonvolatile memory is made valid by a general-purpose logic, and when writing to a electrically rewritable nonvolatile memory is in valid and the operation panel and the FPGA perform a serial communication and in a case where the data order of the serial communication is the predetermined data order, the CPU controls the electrically rewritable nonvolatile memory, and rewriting data, which is outputted from the operation panel, to the electrically rewritable nonvolatile memory is transmitted from the FPGA to the electrically rewritable nonvolatile memory so as to rewrite the data in the electrically rewritable nonvolatile memory. | 09-19-2013 |
| 20130259182 | TRAVELING REACTOR POWER MONITORING SYSTEM AND METHOD FOR CONTROLING RETRACTING A TRAVELING PROBE - A traveling reactor power monitoring system includes a traveling reactor power monitoring system including a drive control unit configured to move a traveling probe in a guide tube by rotating a motor, and a proximity switch that generates a 1st preventing retraction signal when the travelling probe is detected by the proximity switch to exist at a predefined stop range in a shielding vessel. The drive control unit stops retracting the travelling probe when the 1st preventing retraction signal is generated by the proximity switch, and wipes out the 1st preventing retraction signal by detecting that the probe exists outside the predefined stop range on the basis of a probe information as a substitute for the 1st preventing retracting signal output by the proximity switch. | 10-03-2013 |
| 20130279640 | INCORE INSTRUMENTATION CABLE ROUTING FOR PRESSURIZED WATER REACTOR - A pressure vessel includes upper and lower vessel sections joined by a flanged connection. A nuclear reactor core includes an array of fuel assemblies comprising fissile material. The nuclear reactor core is disposed in the lower vessel section. A side-entry vessel penetration is located at a side of the pressure vessel and passes through one of (i) a flange of the flanged connection and (ii) the lower vessel section. An incore instrument routing tube extends from the side-entry vessel penetration and enters the reactor core from above the reactor core. The incore instrument routing tube extends from the side-entry vessel penetration with a declination angle A | 10-24-2013 |
| 20130287159 | CORE MONITORING SYSTEM - A core monitoring system including: a TIP measuring a neutron amount in a nuclear reactor; a TIP drive device; a TIP panel; a neutron monitoring panel; and a process computer. The TIP panel includes: a TIP level processor and a TIP position processor that process a TIP level signal and a TIP position signal input from the TIP drive device, respectively; a time setting section synchronizing the TIP level signal and the TIP position signal; and a TIP level data storage section storing synchronized TIP level data. The neutron monitoring panel includes a time setting section setting collecting time of a LPRM level signal and an APRM level signal. The process computer compares the time and stores the TIP level data from the TIP panel and the LPRM and APRM level signals from the neutron monitoring panel corresponding in time, and calculates core performance based on the TIP level data. | 10-31-2013 |
| 20130336439 | NEUTRON FLUX DETECTOR GUIDING APPARATUS - In a neutron flux detector guiding apparatus, a cylindrical support column is erected on an upper core support plate of a nuclear reactor container main body, a plurality of guide thimble guiding tubes is provided inside the upper core support column between the upper core support plate and an upper core plate, a plurality of guide thimbles is extended from the support column into the guide thimble guiding tubes, the plurality of guide thimbles is supported by a support plate supported at one end part by the support column and erected at the other end part by a support leg above the upper core support plate, and an upper end part of the support plate is inclined downward from the support column side toward the support leg side, thereby realizing simplification of a structure. | 12-19-2013 |
| 20140050290 | METHOD OF CONSTRUCTING PSEUDO HOT PIN POWER DISTRIBUTION USING IN-CORE DETECTOR SIGNAL-BASED PLANAR RADIAL PEAKING FACTORS IN CORE OPERATING LIMIT SUPERVISORY SYSTEM - Disclosed herein is a method for constructing a pseudo hot pin power distribution using in-core detector signal-based planar radial peaking factors in a Core Operating Limit Supervisory System (COLSS). The method includes defining a planar radial peaking factor F | 02-20-2014 |
| 20140050291 | POWER MONITORING SYSTEM - The power monitoring system has: a local power range monitor (LPRM) unit that has a plurality of local power channels to obtain local neutron distribution in a nuclear reactor core; an averaged power range monitor (APRM) unit that receives power output signals from the LPRM unit and obtains average output power signal of the reactor core as a whole; and an oscillation power range monitor (OPRM) unit that receives the power output signals from the LPRM unit and monitors power oscillations of the reactor core. The output signals from the LPRM unit to the APRM unit and the output signals from the LPRM unit to the OPRM unit are independent. | 02-20-2014 |
| 20140064425 | TRANSVERSE IN-CORE PROBE MONITORING AND CALIBRATION DEVICE FOR NUCLEAR POWER PLANTS, AND METHOD THEREOF - A method and apparatus for the calibration of neutron flux monitoring devices used in a nuclear reactor core. The apparatus includes a transverse in-core probe (TIP) cable with a neutron absorber located a fixed distance apart from a TIP detector. The neutron absorber may be passed within close proximity of the neutron flux monitoring device such that a perceived drop in measured neutron flux occurs, whereupon the cable may be repositioned relative to the monitoring device to ensure that the TIP detector is within close proximity of the monitoring device for purposes of calibrating the monitoring device. | 03-06-2014 |
| 20140105346 | NEUTRON DETECTION APPARATUS - Provided are a neutron detector detecting a neutron flux distribution of the inside of a reactor, a thimble guide tube provided being inserted from outside into inside of the reactor, for inserting the neutron detector, a drive apparatus connected to the thimble guide tube and inserting or extracting the neutron detector into or out of the thimble guide tube, a vacuum unit controlling the vacuum state in the thimble guide tube, a supply unit supplying carbon dioxide gas, a gas purge unit connected to the supply unit and conducting gas purge in the thimble guide tube by carbon dioxide gas, a gate valve provided between the thimble guide tube and the drive apparatus and performing open/close operation, and a control apparatus controlling the gate valve, the drive apparatus, the vacuum unit, the supply unit, and the gas purge unit. | 04-17-2014 |
| 20140133620 | METHOD OF VALIDATING NUCLEAR REACTOR IN-VESSEL DETECTOR OUTPUT SIGNALS - A method to perform signal validation for either reactor fixed incore detectors and/or core exit thermocouples to enhance core monitoring systems. The method uses a combination of both measured sensor signals and expected signal responses to develop a ratio of measured to expected signals. The ratios are evaluated by determining the expected ratios for each detector based on the behavior of the remaining collection of detectors, taking into account the geometry/location of the other detectors. The method also provides for automatic removal of invalid detectors from the core power distribution determination if sufficient detectors remain on line to adequately characterize the core's power distribution. | 05-15-2014 |
| 20140192944 | NEUTRON FLUX MAPPING SYSTEM AND CONTROL METHOD FOR NEUTRON FLUX MAPPING SYSTEM - Provided are a neutron detector for detecting a neutron flux distribution of the inside of a reactor, a drive cable connected to the neutron detector, a drive unit for driving the drive cable, a plurality of guide thimbles provided being inserted from the outside of the reactor into the reactor, for inserting the neutron detector, a storage tube for storing the neutron detector, a path transfer device connected to the drive unit, for selecting one of insertion of the neutron detector into each of the guide thimbles and insertion of the neutron detector into the storage tube, and an inspection guide tube connecting the drive unit and the storage tube. The drive unit has a switching unit for switching between the path transfer device side and the inspection guide tube side. | 07-10-2014 |
| 20140270039 | NUCLEAR RADIATION DOSIMETER USING STRESS INDUCED BIREFRINGENCE CHANGES IN FIBER OPTIC CABLES - The present invention relates to devices and methods for measuring neutron fluence at a pre-selected location which is positioned in a nuclear power plant. The devices and methods include passing neutrons through a fiber optic cable. The fiber optic cable has disposed therein a neutron sensitive material which is capable of absorbing the neutrons to produce a gas. The gas results in a build-up of pressure in the fiber optic cable which causes a change in the optical stress birefringence pattern. This change is measured and used to determine the amount of gas in the fiber optic cable, the number of neutrons absorbed by the neutron sensitive material and subsequently, the neutron fluence at the pre-selected location. | 09-18-2014 |
| 20140348286 | NEUTRON DETECTION USING POISSON DISTRIBUTION COMPARISON INDEPENDENT OF COUNT RATE BASED ON CORRELATION SIGNALS - Embodiments are directed to comparison-based methods of conditionally assessing the excess in correlation of an unknown neutron count measurement compared to the correlation present in a data defined as background, and to providing a technical definition of excess correlation intended to properly handle the measured excess correlation. The degree of correlation between an unknown source and background can be used to prevent masking of neutron count data for the source by background radiation. | 11-27-2014 |
| 20140362966 | Neutron Monitoring System - A neutron monitoring system for monitoring a state of a fuel used in a nuclear power plant includes the following: neutron detector; a structural material to which the neutron detector is mounted; a water detection sensor mounted at a position corresponding to the same height as is the neutron detector, the water detection sensor including a thermocouple and a heating element; an amplification circuit configured to amplify a neutron monitoring signal sent from the neutron detector; a temperature measuring circuit connected to a thermocouple of the water detection sensor via strands; a heater power supply connected to a heating element of the water detection sensor via heater lead wires; a water existence determining control section configured to determine whether the water detection sensor is underwater; and a correction circuit configured to correct an output signal value of the amplification circuit in accordance with a determination signal from the water existence determining control section. | 12-11-2014 |
| 20150055742 | Ion Chamber Radiation Detector - An in-core nuclear detector for detecting the neutron population surrounding the detector. The detector is an ion chamber having a cylindrical outer electrode that is insulated from a central electrode and capped to contain an Argon gas. An electron radiator that produces prompt neutron capture gamma radiation that is substantially, directly proportional to the local neutron population is disposed between the outer tubular electrode and the central electrode. | 02-26-2015 |
| 20150146837 | OSCILLATION POWER RANGE MONITOR SYSTEM AND A METHOD OF OPERATING A NUCLEAR POWER PLANT - According to an embodiment, an oscillation power range monitor system has a plural of OPRM units. Each of the OPRM units has: the receiving cell-output set signals and averaging the cell-output set signals; a time average calculating unit calculating a time average cell value; a normalized cell value calculating unit calculating a normalized cell value; a trip determining unit outputting a reactor trip signal if amplitude or growth rate of oscillation or period of oscillation of the normalized cell value has exceeded a prescribed condition; a signal and prescribed value adjusting unit adjusting the relation between the normalized cell value and the specific value, thereby compensating for the deterioration in the neutron flux sensitivity of any LPRM detector in order to keep outputting the reactor trip signal. | 05-28-2015 |
| 20150348655 | STABILITY COMPUTATION MONITORING DEVICE, REACTOR POWER STABILITY MONITORING SYSTEM AND REACTOR POWER STABILITY MONITORING METHOD - According to one embodiment, a stability computation monitoring device monitors in real time reactor power oscillation based on signals from neutron detectors. The device has: a detection sampling section sampling signals from the plurality of neutron detectors to output a detection sampling signal for each neutron detector; a local power monitoring section converting the detection sampling signal into a neutron flux signal; a low-pass filter applying low-pass filtering to neutron flux signal; a down-sampling section performing down-sampling for the neutron flux signals that have passed through the low-pass filter at a period longer than the detection sampling period; a wavelet transformation section applying Discrete Wavelet transformation to the neutron flux signals that have been subjected to the down-sampling to compute a DWT wavelet coefficient of each level; and a monitoring section monitoring the wavelet coefficient computed by the wavelet transformation section. | 12-03-2015 |
| 20150348656 | NEUTRON FLUX LEVEL MEASUREMENT SYSTEM, NEUTRON FLUX LEVEL COMPUTING DEVICE AND NEUTRON FLUX LEVEL MEASUREMENT METHOD - According to one embodiment, a neutron flux level computing component has: an analog signal processing system that amplifies an AC component of a detector output signal from a neutron detector and performs filtering for removal of a high-frequency component; a digitization system that converts, at a certain sampling period, an output signal from the analog signal processing system into a digital time-series signal; a wavelet analysis system that performs discrete wavelet transformation using the digital time-series signal to compute a wavelet coefficient; and a digital signal processing system that computes a mean square value of the wavelet coefficients and converts the computed mean square value into a neutron flux level value. | 12-03-2015 |
| 20150364225 | METHOD OF SYNTHESIZING NUCLEAR REACTOR POWER DISTRIBUTION USING OPTIMIZED NONLINEAR BASIS FUNCTION - Disclosed herein is a method of synthesizing nuclear reactor power distribution using an optimized nonlinear basis function by means of combining signals of neutron detectors provided inside or outside a nuclear reactor. The method includes searching an optimized basis function combination, without determining previously a shape of a basis function, in such a way that error occurrence is minimized, and determining a shape of a synthesis function. When searching the optimized basis function combination and determining the shape of the synthesis function, the following equation is used. | 12-17-2015 |
| 20160180977 | NEUTRON MEASUREMENT APPARATUS AND NEUTRON MEASUREMENT METHOD | 06-23-2016 |
| 376255000 | Directly generating electrical signal (e.g., ion detection) | 7 |
| 20100067643 | High dielectric insulated coax cable for sensitive impedance monitoring - A boiling water reactor core power level monitoring system includes a desired length of high dielectric, non-linear material insulated coaxial type cable in close proximity to the reactor core and a time domain reflectometry apparatus configured to measure a temporary characteristic impedance change associated with the coaxial type cable in response to at least one of neutron or gamma irradiation generated via the reactor core. | 03-18-2010 |
| 20100303190 | METHOD OF PRODUCING MIXED IN-CORE MAPS AND APPLICATION TO THE CALIBRATION OF FIXED INSTRUMENTATION - The object of the present invention is a method for establishing so-called “mixed IN-CORE mappings”. Its essential purpose is to compensate a loss of density of a reference instrumentation, called “RIC instrumentation” (or “RIC system”), when a significant number of locations, initially used by the sensors of the RIC system, are occupied by fixed collectron-type rods. An obvious physical interest lies in the increase of the measurement density, and thus of the level of confidence, associated with the operating results deduced from the processing of these measurements. One application of the method according to the invention concerns a collectron-type detector calibration method placed inside a nuclear reactor core. | 12-02-2010 |
| 20110274230 | DEVICE FOR ONLINE MEASUREMENT OF A FLOW OF FAST AND EPITHERMAL NEUTRONS - A device for online measurement of a flow of fast and epithermal neutrons. The device has a fast and epithermal neutron detector (DNR) able to detect principally fast and epithermal neutrons; a thermal neutron detector (DNT) able to detect principally thermal neutrons; a first circuit (C | 11-10-2011 |
| 20120121054 | APPARATUS FOR INSPECTING AND TESTING STARTUP RANGE NEUTRON MONITORING SYSTEM - An apparatus for inspecting and testing a startup range neutron monitoring system for a nuclear reactor. The apparatus includes: a neutron-flux detector; a preamplifier that amplifies an electric signal output from the neutron-flux detector; a pulse measurement unit that counts times when electric signal output from the preamplifier exceeds a discrimination voltage; a discrimination-voltage setting unit that applies the discrimination voltage to the pulse measurement unit; a voltage-setting unit that applies a voltage to the neutron-flux detector; an arithmetic processing unit that calculates an output power of the reactor based upon an output signal of the pulse measurement unit; an output unit that outputs data representing the output power of the reactor, calculated by the arithmetic processing unit; and an inspecting/testing unit that sets the discrimination voltage and the voltage to be applied by the voltage-setting unit. | 05-17-2012 |
| 20120177167 | SELF-POWERED WIRELESS IN-CORE DETECTOR - A method and apparatus for monitoring a parameter in an irradiated environment and communicating a signal representative of the monitored parameter to a less caustic environment that employs a wireless transmitter that is powered by the irradiated environment. The power for the wireless transmitter is derived from a self-powered radiation detector disposed within the radioactive environment. | 07-12-2012 |
| 20140270040 | SYSTEMS AND METHODS FOR SPENT FUEL POOL SUBCRITICALITY MEASUREMENT AND MONITORING - A system and method for measuring and monitoring axial flux to determine subcriticality in a spent fuel pool of a nuclear power plant. In certain embodiments of this invention, one or more neutron detectors are operable to generate signals resulting from neutron interactions in the spent fuel pool, a counting device counts the signals which are generated by the one or more neutron detectors, a connecting means electrically connects the one or more neutron detectors to the counting device, a signal analyzer is used to determine reactivity of the fuel assemblies in the spent fuel pool based on the counted signals, a power supply provides power for the neutron detectors, the counting device and the system analyzer, and a software code containing an axial flux curve index is used to correlate the counted signals to determine the subcriticality of the spent fuel pool. | 09-18-2014 |
| 20140321592 | SELF POWERED NUCLEAR DETECTOR - A self-powered neutron detector having an emitter with a slightly negative bias voltage that assures that an increase in the electrons that enter the insulator are counted and decreases or eliminates the gamma induced prompt signal. Variations in the size of the bias is used as a diagnostic tool to estimate the gamma induced prompt signal. | 10-30-2014 |
