Directly Generating Electrical Signal (e.g., Ion Detection) Patents (Class 376/255)
  • Patent number: 11114210
    Abstract: A control rod operation generates a rod insertion block signal during operation of a reactor. Four neutron detector assemblies including a plurality of LPRMs arranged in an axial direction of a core are arranged adjacent to a plurality of insertion selection control rods, respectively, which are simultaneously inserted into the core. Neutron flux ratio calculation units are arranged in each of the neutron detector assemblies, and ratios (neutron flux ratios BA/AA, CA/AA, and DA/AA) of an average LPRM signal of the respective LPRMs at positions B, C, and D to an average LPRM signal of the respective LPRMs at a position A which is closest to the control rod insertion end of the core are calculated. When the largest neutron flux ratio out of the neutron flux ratios exceeds a set neutron flux ratio, a rod insertion block signal which is generated by a local range rod insertion monitor is output.
    Type: Grant
    Filed: November 25, 2016
    Date of Patent: September 7, 2021
    Assignee: HITACHI-GE NUCLEAR ENERGY, LTD.
    Inventors: Koji Matsumoto, Kazuya Ishii, Takao Kondou, Akira Konoma, Akiyuki Tsuchiya
  • Patent number: 9576688
    Abstract: Illustrative embodiments provide for the operation and simulation of the operation of fission reactors, including the movement of materials within reactors. Illustrative embodiments and aspects include, without limitation, nuclear fission reactors and reactor modules, including modular nuclear fission reactors and reactor modules, nuclear fission deflagration wave reactors and reactor modules, modular nuclear fission deflagration wave reactors and modules, methods of operating nuclear reactors and modules including the aforementioned, methods of simulating operating nuclear reactors and modules including the aforementioned, and the like.
    Type: Grant
    Filed: September 23, 2009
    Date of Patent: February 21, 2017
    Assignee: TerraPower, LLC
    Inventors: Jon D. McWhirter, Thomas Allan Weaver, Charles Whitmer, Lowell L. Wood, Jr., George B. Zimmerman
  • Patent number: 9570205
    Abstract: A radiation monitoring device comprises a radiation monitor and a test unit for testing the radiation monitor. The radiation monitor includes a radiation detector and a measurement unit. The test unit includes a test pulse generator and a test pulse controller. The measurement unit includes a counter circuit, a computing part that computes a count rate with the standard deviation kept constant, an input switching circuit. When a test mode is selected in the radiation monitor, the test pulse controller changes the repetition frequency of test pulses in a step-function manner to the same repetition frequency of a start count rate specified as reference, replaces a count rate in the computing part at current computing cycle with the start count rate, switches the input switching circuit to the test pulse input at next computing cycle to start the test, and then finishes the test after a predetermined time elapses.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: February 14, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Shohei Katayama, Kenichi Moteki
  • Patent number: 9373423
    Abstract: A telescoping guide for extraction and reinsertion support handling of in-core instrument thimble assemblies in the area above the upper support plate in the upper internals of a pressurized water reactor. The telescoping guides extend between the upper ends of the upper internals support columns and an axially movable instrumentation grid assembly which is operable to simultaneously raise the telescoping guides and extract the in-core instrument thimble assemblies from the reactor fuel assemblies.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: June 21, 2016
    Assignee: Westinghouse Electric Company LLC
    Inventors: Eric M. Weisel, Kenneth V. Margotta, Daniel Walus, Thomas J. Schildkamp, Joseph J. Hahn, Michael D. Heibel
  • Patent number: 9251920
    Abstract: A system for monitoring a state of a reactor core in a nuclear reactor may include an internal monitoring device located inside the reactor core, the internal monitoring device including one or more internal sensor arrays configured to take measurements of conditions of the reactor core at different vertical regions within the reactor core to generate internal measurement data; an external monitoring device located in the reactor structure outside the reactor core, the external monitoring device including one or more external sensor arrays configured to take measurements of conditions of the reactor core at positions outside the reactor core corresponding the plurality of different vertical regions within the reactor core to generate external measurement data, and a transmitter configured to wirelessly transmit the external measurement data; and a receiver station configured to determine a state of the reactor core based on the external and internal measurement data.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: February 2, 2016
    Assignee: GE-HITACHI NUCLEAR ENERGY AMERICA LLC
    Inventors: Eric P. Loewen, Brian S. Triplett, Brett J. Dooies
  • Patent number: 9208907
    Abstract: 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.
    Type: Grant
    Filed: February 20, 2013
    Date of Patent: December 8, 2015
    Assignee: Westinghouse Electric Company LLC
    Inventors: David J. Krieg, William A. Boyd, Nicholas A. Bachmann
  • Patent number: 9207335
    Abstract: 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.
    Type: Grant
    Filed: April 29, 2013
    Date of Patent: December 8, 2015
    Assignee: Westinghouse Electric Company LLC
    Inventors: Frank D. Popa, Stuart M. McDonald
  • Patent number: 9025719
    Abstract: 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.
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: May 5, 2015
    Assignee: GE-Hitachi Nuclear Energy Americas LLC
    Inventor: James Edward Fawks, Jr.
  • Patent number: 8964926
    Abstract: 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.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: February 24, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shingo Nakamura, Tatsuro Kobayashi
  • Publication number: 20140321592
    Abstract: 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.
    Type: Application
    Filed: April 29, 2013
    Publication date: October 30, 2014
    Applicant: Westinghouse Electric Company LLC
    Inventors: Frank D. Popa, Stuart M. McDonald
  • Publication number: 20140270040
    Abstract: 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.
    Type: Application
    Filed: June 3, 2013
    Publication date: September 18, 2014
    Applicant: Westinghouse Electric Company LLC
    Inventor: Westinghouse Electric Company LLC
  • Patent number: 8804894
    Abstract: 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.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: August 12, 2014
    Assignee: Areva NP
    Inventor: Gérard Rio
  • Patent number: 8767903
    Abstract: 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.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: July 1, 2014
    Assignee: Westinghouse Electric Company LLC
    Inventors: John G. Seidel, Robert W. Flammang, Jorge V. Carvajal, Michael A. James, Nicola G. Arlia
  • Patent number: 8712000
    Abstract: 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.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: April 29, 2014
    Assignee: Global Nuclear Fuel—Americas, LLC
    Inventor: James Edward Fawks, Jr.
  • Patent number: 8681920
    Abstract: 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.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: March 25, 2014
    Assignee: Westinghouse Electric Company LLC
    Inventors: Michael D. Heibel, Daniel P. Kistler, Michael C. Prible, Jorge V. Carvajal, Jason Palmer
  • Patent number: 8483347
    Abstract: In a pressurized water reactor with all of the in-core instrumentation gaining access to the core through the reactor head, each fuel assembly in which the instrumentation is introduced is aligned with an upper internals instrumentation guide-way. In the elevations above the upper internals upper support assembly, the instrumentation is protected and aligned by upper mounted instrumentation columns that are part of the instrumentation guide-way and extend from the upper support assembly towards the reactor head in hue with a corresponding head penetration. The upper mounted instrumentation columns are supported laterally at one end by an upper guide tube and at the other end by the upper support plate.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: July 9, 2013
    Assignee: Westinghouse Electric Company LLC
    Inventors: Norman R. Singleton, David A. Altman, Ching Yu, James A. Rex, David R. Forsyth
  • Patent number: 8442181
    Abstract: 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.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: May 14, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hideyuki Kitazono
  • Patent number: 8433029
    Abstract: In one embodiment, the method includes determining the safety limit minimum critical power ratio using the operating limit minimum critical power ratio, a change-in-critical-power-ratio distribution bias and a change-in-critical-power-ratio distribution standard deviation.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: April 30, 2013
    Assignee: Global Nuclear Fuel—Americas, LLC
    Inventor: James Edward Fawks, Jr.
  • Patent number: 8406368
    Abstract: An upper detector and a lower detector that face at least one side of a fuel assembly, on which neutrons are irradiated in a nuclear reactor, and detect radiation are set at a predetermined interval in an axial direction of the fuel assembly. Distributions of radiation signals are measured by the upper detector and the lower detector while the fuel assembly and the upper detector and the lower detectors are relatively moved along the axial direction of the fuel assembly. Soundness of radiation signals measured by the upper detector and the lower detector is determined in every measurement by comparing radiation signal distributions obtained by measuring the same portion in the axial direction of the fuel assembly in a multiplexed manner with the upper detector and the lower detector. Thereafter, relative burn-up is calculated by utilizing the measured radiation signals to measure a burn-up profile.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: March 26, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hironori Kumanomido, Naotaka Oda, Yutaka Tokiwa, Makoto Ueda
  • Patent number: 8401141
    Abstract: A first intensity Az expressed as Az=az×E?, a first reference intensity A0 expressed as A0=a0×E?, a second intensity Bz expressed as Bz=bz×E, and a second reference intensity B0=b0×E, are evaluated. The first intensity and the first reference intensity are of radioactive nuclides generated by a neutron capture reaction of a heavy nuclide or a fission product nuclide. The second intensity and the second reference intensity are of radioactive fission product nuclides except nuclides generated by a neutron capture reaction. The reference intensities are measured where the void fraction is known. Also a correlation curve of (az/a0) and a void fraction is evaluated. Finally an axial void fraction distribution is evaluated based on the value of (az/a0) and the correlation curve.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: March 19, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Makoto Ueda, Hironori Kumanomido, Ishi Mitsuhashi, Tsukasa Kikuchi, Kenichi Yoshioka, Tomoharu Sasaki, Kouji Hiraiwa
  • Patent number: 8238509
    Abstract: 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?1 seconds and less than 5×105 seconds.
    Type: Grant
    Filed: September 11, 2009
    Date of Patent: August 7, 2012
    Assignee: GE-Hitachi Nuclear Energy Americas LLC
    Inventors: Stephan Craig Moen, Craig Glenn Meyers, John Alexander Petzen, Adam Muhling Foard
  • Patent number: 8223913
    Abstract: A method for measuring high-energy radiation includes applying a voltage pulse to electrodes in an ion chamber filled with a gas capable of forming charged ions by the high-energy radiation; measuring an ion current signal related to ion currents induced by the voltage pulse; and determining a magnitude of the high-energy radiation based on the ion current signal.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 17, 2012
    Assignee: Thermo Fisher Scientific Inc.
    Inventors: Michael Masterov, Alexander Joseph Esin
  • Publication number: 20120177167
    Abstract: 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.
    Type: Application
    Filed: January 7, 2011
    Publication date: July 12, 2012
    Applicant: WESTINGHOUSE ELECTRIC COMPANY LLC
    Inventors: Michael D. Heibel, Daniel P. Kistler, Michael C. Prible, Jorge V. Carvajal, Jason Palmer
  • Publication number: 20120121054
    Abstract: 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.
    Type: Application
    Filed: January 24, 2012
    Publication date: May 17, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Hideyuki KITAZONO
  • Patent number: 8116421
    Abstract: 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.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: February 14, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hideyuki Kitazono
  • Publication number: 20110274230
    Abstract: 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 (C1) for processing the signal delivered by the fast neutron detector; a second circuit (C2) for processing the signal delivered by the thermal neutron detector; a means (CE, PMM) suitable for determining the progressive sensitivity to the fast neutrons and to the thermal neutrons of each of the neutron detectors, and a computer (CALC) which computes the flow of fast and epithermal neutrons on the basis of the said progressive sensitivities and of the signals delivered by the first and second processing circuits.
    Type: Application
    Filed: October 9, 2009
    Publication date: November 10, 2011
    Applicants: SCK.CEN, COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
    Inventors: Ludovic Oriol, Bernard Lescop, Ludo Vermeeren
  • Publication number: 20110085633
    Abstract: A method of monitoring a condition of a nuclear reactor pressure vessel disposed in a radioactive environment is provided. The method includes the steps of sensing a condition of the reactor pressure vessel with an instrument, transmitting a signal indicative of the condition of the reactor pressure vessel from the instrument to a powered wireless transmitting modem disposed in the radioactive environment, wirelessly transmitting a signal indicative of the condition of the reactor pressure vessel from the transmitting modem to a receiving modem in the line of sight of the transmitting modem, transmitting a signal indicative of the condition of the reactor pressure vessel from the receiving modem to a signal processing unit, and determining the condition of the reactor pressure vessel from the wirelessly transmitted signal.
    Type: Application
    Filed: October 13, 2009
    Publication date: April 14, 2011
    Applicant: Westinghouse Electric Company
    Inventor: Richard W. Morris
  • Patent number: 7894565
    Abstract: 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.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: February 22, 2011
    Assignee: Westinghouse Electric Company LLC
    Inventors: Michael D. Heibel, Patrick J. Sebastiani, Stanwood L. Anderson
  • Publication number: 20100303190
    Abstract: 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.
    Type: Application
    Filed: October 9, 2008
    Publication date: December 2, 2010
    Inventor: Gérard Rio
  • Publication number: 20100067643
    Abstract: 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.
    Type: Application
    Filed: September 16, 2008
    Publication date: March 18, 2010
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Daniel Qi Tan, Michael Joseph Krok
  • Patent number: 7532698
    Abstract: Systems and methods for a method for determining a critical effective k at an off-rated core state of a nuclear power plant includes determining, for the off-rated core state a control rod density, a percent core power, a gadolinium reactivity worth, a doppler reactivity worth, and a xenon reactivity worth responsive to a control rod pattern, a reactor power plan including the off-rated core state, and a reference effective k, calculating a change in an effective k from the reference effective k at the off-rated core state responsive to two or more parameters selected from the group consisting of the control rod density, the percent core power, the gadolinium reactivity worth, the doppler reactivity worth, and the xenon reactivity worth, and generating the critical effective k for the off-rated core state responsive to the change in the effective k from the reference effective k.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: May 12, 2009
    Assignee: Global Nuclear Fuel - Americas, LLC
    Inventors: Ugur Mertyurek, David Joseph Kropaczek, Atul A. Karve, Angelo P. Chopelas
  • Patent number: 7368726
    Abstract: A method for measuring high-energy radiation flux includes applying a positive voltage to electrodes in an ion chamber filled with a gas capable of forming charged ions by a high-energy radiation, measuring a positive ion current signal related to ion currents induced by the positive voltage, applying a negative voltage to the electrodes, measuring a negative signal related to ion currents induced by the negative voltage, and determining a magnitude of the high-energy radiation flux based on the ion current signal.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: May 6, 2008
    Assignee: Thermo Fisher Scientific Inc.
    Inventors: Alexander Joseph Esin, Michael Masterov
  • Patent number: 7333585
    Abstract: A radiation measurement device includes a radiation detector generating an analog signal containing pulse components, an A/D converter converting the analog signal into sampled data, an n-th power pulse discrimination unit calculating n-th power values of the sampled data to discriminate the pulse component, where n is two or more, and a pulse counter counting a number of the discriminated pulse components.
    Type: Grant
    Filed: February 7, 2006
    Date of Patent: February 19, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mikio Izumi, Masafumi Yamada, Tatsuyuki Maekawa, Teruji Tarumi
  • Patent number: 7222061
    Abstract: In the method, a set of limits applicable to a test rod pattern design are defined, and a sequence strategy for positioning one or more subsets of the test rod pattern design is established. Reactor operation on a subset of the test rod pattern design, which may be a subset of fuel bundles in a reactor core for example, is simulated to produce a plurality of simulated results. The simulated results are compared against the limits, and data from the comparison is provided to indicate whether any of the limits were violated by the test rod pattern design during the simulation. A designer or engineer may use the data to determine which operator parameters need to be adjusted (e.g., control blade notch positions for example) in order to create a derivative rod pattern design for simulation, and eventually perfect a rod pattern design for a particular core.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: May 22, 2007
    Assignee: Global Nuclear Fuel - Americas, LLC
    Inventors: William Earl Russell, II, David Joseph Kropaczek, Steven Barry Sutton, Christian Carlos Oyarzun, William Charles Cline, Carey Reid Merritt
  • Patent number: 7139354
    Abstract: A radiation measurement device includes a radiation detector generating an analog signal containing pulse components, an A/D converter converting the analog signal into sampled data, an n-th power pulse discrimination unit calculating n-th power values of the sampled data to discriminate the pulse component, where n is two or more, and a pulse counter counting a number of the discriminated pulse components.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: November 21, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mikio Izumi, Masafumi Yamada, Tatsuyuki Maekawa, Teruji Tarumi
  • Patent number: 6836523
    Abstract: A radiation measurement device includes a radiation detector generating an analog signal containing pulse components, an A/D converter converting the analog signal into sampled data, an n-th power pulse discrimination unit calculating n-th power values of the sampled data to discriminate the pulse component, where n is two or more, and a pulse counter counting a number of the discriminated pulse components.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: December 28, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mikio Izumi, Masafumi Yamada, Tatsuyuki Maekawa, Teruji Tarumi
  • Patent number: 6801593
    Abstract: A method of monitoring reactivity changes in a nuclear reaction when the nuclear reaction is subcritical. The method controls the parameter of the nuclear reaction that affects reactivity of the reaction to slightly alter the reactivity while monitoring an output of a source range detector. The Inverse Count Rate Ratio from the output of the detector is determined periodically during a transient portion of the output. A correction factor is applied to the Inverse Count Rate Ratio data and the data is plotted as a function of time. The correction factor linearizes the Inverse Count Rate Ratio data so that the curve can be predictably extrapolated.
    Type: Grant
    Filed: November 21, 2002
    Date of Patent: October 5, 2004
    Assignee: Westinghouse Electric Company LLC
    Inventors: Yung-An Chao, Donald James Hill, Michael David Heibel, Jeffrey Robert Secker
  • Patent number: 6744840
    Abstract: An incore monitoring method of a nuclear reactor, includes, measuring neutron flux levels at pitch levels corresponding to local power range monitor sensors arranged along an axial direction inside a detector assembly installed in a nuclear reactor; performing power calculation, including calculation of thermal characteristics, of fuel assembly group consisting of fuel assemblies adjacent to the corresponding detector assembly, based on indicated values of the local power range monitor sensors of the corresponding detector assembly at a first time, calculating thermal characteristics at a second, subsequent time in which the power calculation is not calculated, based on values indicated by the local power range monitor sensors and calculated thermal characteristics at the first time and values indicated by the corresponding local power range monitor sensors at the second time, and monitoring the calculated thermal characteristics.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: June 1, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiji Karino, Jun Hamada
  • Patent number: 6535568
    Abstract: A method and system for demonstrating compliance of nuclear fuel rods with fundamental licensing criteria for fuel rod internal pressure during nuclear reactor operation is presented. A nuclear fuel rod evaluation process is performed during the fuel cycle design and licensing process for each operating cycle of a particular nuclear reactor. The evaluation process includes a rod-by-rod internal pressure analysis based on empirical data of actual operational power output levels of each fuel rod in the reactor core. A computer program constructs individual fuel rod power histories for each nuclear fuel rod in the reactor core based on empirical information acquired during previous fuel cycles and the projected operation of the reactor in an upcoming fuel cycle. Using the constructed power histories for each fuel rod, the program then computes thermal and mechanical overpower limits and a maximum internal pressure for each rod in the upcoming fuel cycle.
    Type: Grant
    Filed: October 4, 2000
    Date of Patent: March 18, 2003
    Assignee: Global Nuclear Fuel -- Americas LLC
    Inventor: Anthony P. Reese
  • Patent number: 6522709
    Abstract: A protective hose, and a method of making the same, for an in-core instrument assembly used in a nuclear reactor, including a first end that is hermetically sealed to a first member of in-core instrument assembly such as a bullet nose, a second end that is hermetically sealed to a second member of said in-core instrument assembly such as a seal plug, and a body portion that surrounds at least one detector in the in-core instrument assembly, and has flexible, corrugated outer and inner surfaces. The body portion includes a series of ribs having peaks. The hose is compacted in length to a degree that the peaks of the ribs are substantially adjacent to one another. The ribs also have side surfaces that decline from the peaks to valley portions that are disposed between the side surfaces. The hose is compacted in length to a degree that the side surfaces are completely in physical contact with one another.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: February 18, 2003
    Assignee: Westinghouse Electric Company LLC
    Inventors: Patrick A. Hellandbrand, Jr., Kenneth V. Margotta, Michael J. Sponzo
  • Patent number: 6477218
    Abstract: A control system, and a control method, of a nuclear power plant capable of easily executing automatic output regulation by an automatic power regulator system even when a lower-accuracy maximum linear heat generation rate and a lower-accuracy minimum critical power ratio are determined in a short cycle by using brief calculation. While a core monitoring system does not calculate a maximum linear heat generation rate and a minimum critical power ratio, they are determined by utilizing the maximum linear heat generation rate and the minimum critical power ratio calculated by the core monitoring system as well as plant data, and the lower-accuracy maximum linear heat generation rate and the lower-accuracy minimum critical power ratio so determined are compared with predetermined thermal limit values.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: November 5, 2002
    Assignee: Hitachi, Ltd.
    Inventor: Yukihisa Fukasawa
  • Patent number: 6477219
    Abstract: A nuclear reactor instrumentation system including a plurality of incore nuclear instrumentation assemblies arranged in a gap between a number of fuel assemblies charged in a reactor core. The incore nuclear instrumentation assemblies each include a fixed type neutron detector having a plurality of fixed type neutron detectors dispersively arranged in a core axial direction and a fixed type gamma thermometer assembly having a plurality of fixed type gamma ray heat detectors arranged at least in a same core axial direction as the fixed type neutron detectors. A power range detector signal processing device operatively connected to the fixed type neutron detector assemblies through signal cables. A gamma thermometer signal processing device is operatively connected to the fixed type gamma thermometer assembly of the incore nuclear instrumentation assembly through a signal cable.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: November 5, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Hirukawa, Shungo Sakurai, Takafumi Naka
  • Patent number: 6430247
    Abstract: Neutron flux is measured using a subset of detectors (8) selected from a set of detectors (8) introduced into fuel assemblies (2) of the core (1) to obtain measurement signals, the number n of detectors (8) of the subset being at most equal to 15% of the number of fuel assemblies (2) in the core (1), the measurement signals are processed and the instantaneous distribution of the neutron flux in the core (1) is calculated allowing for the measurement signals. At least one operating parameter of the core is calculated from the instantaneous neutron flux distribution, and an alarm is triggered if at least one parameter is outside a fixed range. The operation of the core of the nuclear reactor can therefore be monitored virtually in real time. The neutron flux detectors (8) introduced into the fuel assemblies of the core preferably include measuring probes consisting of collectrons.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: August 6, 2002
    Assignee: Framatome
    Inventors: Jean-Lucien Mourlevat, Norque Louedec
  • Patent number: 6406064
    Abstract: A locking device for a reactor instrumentation protective sleeve and reactor instrumentation column assembly. The locking device includes a protective sleeve coupled to the instrumentation column by a selectively operable and closeable clip assembly. The locking device also includes a locking sleeve supported by the protective sleeve. The locking sleeve is supported by the protective sleeve such that a portion of the locking sleeve covers a portion of the protective sleeve and the clip assembly.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: June 18, 2002
    Assignee: Westinghouse Electric Company LLC
    Inventor: Richard W. Morris
  • Patent number: 6400786
    Abstract: During operation of the nuclear reactor, at specified time intervals, a neutron flux is measured using a set of neutron flux detectors which are fixed and arranged in the core (1) of the nuclear reactor, the maximum number n of detectors (8) being 15% of the number of fuel assemblies in the core. The measured signals are processed and the instantaneous distribution of neutron flux or of power throughout the entire core (1) is calculated from the measured signals. At least one core operating parameter is calculated from the instantaneous neutron flux distribution and an alarm is raised if at least one parameter exceeds a set range.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: June 4, 2002
    Assignee: Framatome
    Inventors: Jean-Lucien Mourlevat, Monique Lovedec
  • Patent number: 6339629
    Abstract: In a system for monitoring power of a nuclear reactor, a plurality of neutron flux measuring devices are arranged in a reactor core of the nuclear reactor for measuring neutron flux so as to generate neutron flux signals on the basis of the measured neutron flux. The neutron flux signals are filtered through a first weighting coefficient and a second weighting coefficient previously held in a monitoring signal calculating unit so as to generate stability monitoring signals. The first weighting coefficient corresponds to a fundamental mode of a neutron flux distribution in the reactor core and tire second weighting coefficient corresponds to a higher mode of the neutron flux distribution therein. The stability monitoring signal filtered through the first and second weighting coefficients are transmitted to a stability monitoring unit the stability monitoring unit monitors the stability of the core according to the transmitted stability monitoring signals.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: January 15, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yutaka Takeuchi, Shigeru Kanemoto, Mitsuhiro Enomoto, Shiho Miyamoto
  • Publication number: 20010026603
    Abstract: A reactor nuclear instrumentation system comprises: a plurality of incore nuclear instrumentation assemblies arranged in a gap between a number of fuel assemblies charged in a reactor core, the incore nuclear instrumentation assemblies each including a fixed type neutron detector assembly comprising a plurality of fixed type neutron detectors dispersively arranged in a core axial direction and a fixed type gamma thermometer assembly comprising a plurality of fixed type &ggr;-ray heat detectors arranged at least in a same core axial direction as the fixed type neutron detectors; a power range detector signal processing device operatively connected to the fixed type neutron detector assemblies through signal cables; and a gamma thermometer signal processing device operatively connected to the fixed type gamma thermometer assembly of the incore nuclear instrumentation assembly through a signal cable.
    Type: Application
    Filed: March 19, 2001
    Publication date: October 4, 2001
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Koji Hirukawa, Shungo Sakurai, Takafumi Naka
  • Patent number: 6236698
    Abstract: A nuclear reactor instrumentation system including a plurality of in core nuclear instrumentation assemblies arranged in a gap between a number of fuel assemblies charged in a reactor core. The income nuclear instrumentation assemblies each include a fixed type neutron detector assembly having a plurality of fixed type neutron detectors dispersively arranged in a core axial direction and a fixed type gamma thermometer assembly having a plurality of fixed type gamma ray heat detectors arranged at least in a same core axial direction as the fixed type neutron detectors. A power range detector signal processing device is operatively connected to the fixed type neutron detector assemblies through signal cables. A gamma thermometer signal processing device is operatively connected to the fixed type gamma thermometer assembly of the in core nuclear instrumentation assembly through a signal cable.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: May 22, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Hirukawa, Shungo Sakurai, Takafumi Naka
  • Patent number: 5793827
    Abstract: A device for carrying out a surveillance program to monitor the environmental effect of radiation and high-temperature oxygenated water on the shroud material in an operating reactor. The device is a holder containing shroud material specimens and encapsulated neutron flux monitors. The holder is installed on the shroud wall and left in place for a predetermined period of reactor operation time for the purpose of monitoring the neutron fluence effect on the shroud material specimens housed in the holder. The specimen holder is later removed from the reactor. The specimens are removed from the holder and examined in a laboratory to determine any changes in material properties. The specimen holder comprises a bolt-like device having a hollow head and a threaded shaft. The hollow head provides space for material specimens and neutron flux monitors. The specimen holder is attached to the shroud wall by screwing the threaded shaft into a threaded hole in shroud wall.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: August 11, 1998
    Assignee: General Electric Company
    Inventors: Karl Bomann Larsen, Charles Arthur Dalke
  • Patent number: 5774515
    Abstract: A neutron particle measuring apparatus includes a neutron converter to generate alpha rays in response to incidence of neutron, a scintillator to receive as input the alpha rays generated from the neutron converter so as to emit and transmit scintillation, two photoreceptive portions to receive the scintillation through different transmitting paths, and a signal processing portion to measure a neutron distribution depending upon times at which the scintillation can reach the photoreceptive portions according to a time-of-flight method. The single particle measuring apparatus can be used to measure the neutron distribution in the vicinity of a nuclear reactor in a nuclear power plant.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: June 30, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hirotsugu Fujiwara, Kazunori Ikegami, Hiroshi Nishizawa