Class / Patent application number | Description | Number of patent applications / Date published |
376215000 | By electronic signal processing circuitry (e.g., plural redundant circuits) | 38 |
20090116605 | Nuclear reactor rod control mechanism control system - The control system comprises an independent removable power module for each coil of a rod control mechanism equipped with three operating coils supplied from a three-phase current source. The power module is connected in series with the corresponding coil and comprises a rectifier circuit with three thyristors controlled in phase angle by a corresponding regulation circuit according to setpoint current values associated with the coil. A monitoring circuit connected to a display interface displays the current flowing in the coil associated with the power module. In the event of a fault, the module and coil involved are easily detected and replaced without requiring shutdown of the whole of the reactor. | 05-07-2009 |
20120140864 | PROTECTION OF REACTOR CORES FROM UNSTABLE DENSITY WAVE OSCILLATIONS - The present invention provides a method of operating a Boiling Water Reactor, having the steps of analyzing LPRM signals for oscilliatory behavior indicative of neutron-flux-coupled density wave oscillations, determining if oscilliatory behavior is present in the signals; initiating a reactor protective corrective action if the oscilliatory behavior is determined, and in addition, initiating corrective actions if neutron uncoupled oscillations are possible. Detecting the later is performed through analytically determined exclusion zone on the power flow map or by on-line stability calculations for several high power channels. | 06-07-2012 |
20120219101 | METHOD FOR ASSISTING IN THE OPERATION OF A NUCLEAR REACTOR - The present invention relates to a method for assisting in the operation of a nuclear reactor, which comprises the steps of: establishing a request using a man/machine interface ( | 08-30-2012 |
20130028364 | Accelerator-Driven Nuclear System with Control of Effective Neutron Multiplication Coefficent - An accelerator-driven subcritical breeding reactor is operated with a neutron multiplication coefficient as large as possible in order to require a small input power from the accelerator, reducing its dimension and hence its cost and complexity. The beam-generated spallation neutron yield then becomes comparable to the fraction of delayed neutrons from the fissioned elements. This can be exploited to ensure an accurate on-line determination of the reactivity. Resulting changes can be adjusted with the help of neutron absorbing control rods and/or variations of the proton current. In addition, the temperature variations during operation can be continuously monitored and adjusted in order to avoid that the subcritical systems approaches too closely the (delayed) criticality condition and that the neutron multiplication coefficient remains within acceptable limits. | 01-31-2013 |
20130170595 | REACTOR SHUTDOWN TRIP ALGORITHM - A controller for producing a nuclear reactor shutdown system trip signal in response to at least one detector signal. The controller includes a signal conditioning module receiving the at least one detector signal and outputting a measured flux signal. A rate module generates a rate signal from the measured flux signal. A comparator circuit compares the rate signal to a trip setpoint and generates a first trip signal. | 07-04-2013 |
20130177119 | CONTROL DEVICE AND NUCLEAR POWER PLANT CONTROL SYSTEM - A nuclear power plant control system includes control devices, and the control devices | 07-11-2013 |
20130202074 | CONTROL SYSTEM FOR NUCLEAR FACILITY AND CONTROL METHOD FOR NUCLEAR FACILITY (AS AMENDED) - A control system allows controlling a nuclear facility in an evacuation area. The control system includes a control device in ordinary use disposed in a non-evacuation area, an emergency control device—for emergency in the evacuation area, a plant control facility connectable to the control device—and the emergency control device, a signal switching unit that switches from a normal coupling to an emergency coupling based on an emergency switch signal, a first selector switch in the non-evacuation area, a second selector switch-in the evacuation area, an AND circuit configured to output the emergency switch signal to the signal switching unit in the case where the emergency switch signal is input from the first selector switch and the emergency switch signal is input from the second selector switch. | 08-08-2013 |
20130266107 | METHODS FOR PROTECTION OF NUCLEAR REACTORS FROM THERMAL HYDRAULIC/NEUTRONIC CORE INSTABILITY - The invention relates to methods for protecting a nuclear reactor core, such as a boiling water reactor core, from fuel and cladding damage due to thermal hydraulic instability in extended operating power flow conditions and, in particular, when an extended power uprate is implemented. The methods employ existing licensed stability methodologies and incorporated minor changes, e.g., to the Average Power Range Monitor (APRM)-based trip system to preclude operation inside the stability vulnerable region of the power/flow map. The APRM-based trip system is modified to set down the APRM flow-biased scram line when core flow is less than a predetermined core flow to prevent the core from entering an unstable region of operation. | 10-10-2013 |
20130301771 | NUCLEAR POWER PLANT CONTROL SYSTEM AND METHOD OF TESTING NUCLEAR POWER PLANT - A nuclear power plant control system ( | 11-14-2013 |
20140177772 | APPARATUS AND METHOD FOR CONTROLLING GAIN ACCORDING TO RATE OF CHANGE IN WATER LEVEL OF STEAM GENERATOR IN NUCLEAR POWER PLANTS - Provided is an apparatus for controlling a gain according to a water level change rate of a steam generator in nuclear power plants. The apparatus includes a water level variance detector detecting a water level variance of the steam generator, a change rate calculator calculating a water level change rate with respect to the detected water level variance, a compensation value calculator calculating a compensation gain value corresponding to the calculated water level change rate, a reactor power sensor sensing whether or not reactor power corresponds to certain power or less, and a gain compensation controller, when the reactor power corresponds to the certain power or less, outputting a control gain value obtained by combining a general gain value provided to control a proportional-integral (PI) controller with the compensation gain value to the PI controller | 06-26-2014 |
20140314194 | CONTROL METHOD FOR A PRESSURIZED WATER NUCLEAR REACTOR - This invention relates to a control method for a pressurised water nuclear reactor, said reactor comprising a core generating thermal power; means of acquiring magnitudes representative of core operating conditions (thermal power, temperature of the primary coolant); said method comprising a step to regulate the temperature of the primary coolant if the temperature of the primary coolant for a given thermal power is outside a predefined set temperature interval (ΔTREF) depending on the reactor power, said set temperature interval (ΔTREF) being characterised by a variable amplitude (ΔT) on a thermal power range between N % and 100% nominal power, where N is between 0 and 100; a zero amplitude at 100% nominal power; a zero amplitude at N % nominal power; said regulation not taking place while the temperature of the primary coolant is inside said temperature interval (ΔTREF) for a given thermal power. | 10-23-2014 |
20160071622 | SYSTEM FOR CONTROLLING A NUCLEAR REACTOR CORE - The invention relates to a system for the monitoring and control of the core of a nuclear reactor along which N fission chambers CF | 03-10-2016 |
376216000 | Plural sensed different conditions or measured variables correlated | 26 |
20090161810 | Reactor Power Control Apparatus of Natural Circulation Reactor, And Method For Controlling Reactor Power of Natural Circulation Reactor - In the present invention, a reactor power control apparatus of a natural circulation reactor comprises a reactor pressure vessel which circulates cooling water using the density difference of the coolant inside, a feed water pipe which is connected to the reactor pressure vessel and supplies cooling water, a power control section which controls the reactor power using a control rod. The feed water pipe has an ultrasonic thermometer sensor. Driving of the control rod is controlled by the power control section based on the feed water temperature detected by the feed water thermometer. The reactor power control apparatus can detect the temperature of the feed water and perform drive control of the control rod preferentially, and obtain stable reactor power. | 06-25-2009 |
20100119026 | Method for Determining the Three-Dimensional Power Distribution of the Core of a Nuclear Reactor - A method determines a volumetric power distribution of a core of a nuclear reactor using a set of detectors for measuring a neutronic flow provided outside the reactor vessel, and a set of probes for measuring the temperature of the coolant at the outlet of the fuel assemblies. The method comprises the step of determining a first volumetric power distribution using a neutronic calculation code instantaneously solving the diffusion equation and updating the isotopic balance of the core during the fuel depletion based on values of the core operation parameters, and the step of determining a new volumetric power distribution by adjusting the first volumetric power distribution using the measures provided by the sensors for measuring the neutronic flow and provided outside the reactor vessel and by the temperature measuring probes. | 05-13-2010 |
20120099690 | DEVICE FOR MEASURING TEMPERATURE COEFFICIENT OF MODERATOR AND METHOD FOR MEASURING TEMPERATURE COEFFICIENT OF MODERATOR - A moderator temperature coefficient measuring device include a control rod driving device; a reactivity measurement processing unit capable of measuring the reactivity of the reactor; an inflow temperature sensor for sensing the inflow temperature of a reactor coolant flowing into the reactor; an outflow temperature sensor for sensing the outflow temperature of the reactor coolant flowing out of the reactor; an average temperature measurement processing unit for measuring the average temperature from the sensed inflow and outflow temperatures; an power control unit for providing control so that the reactor delivers constant thermal power; and a temperature coefficient calculating unit for calculating the temperature coefficient of the reactor coolant based on the amount of change in reactivity between before and after the insertion of the control rod and the amount of change in average temperature between before and after the insertion of the control rod under the constant thermal power. | 04-26-2012 |
20130294560 | CONTROL ROOM FOR NUCLEAR POWER PLANT - A reactor control interface includes a home screen video display unit (VDU) displaying blocks representing functional components of a nuclear power plant and connecting arrows that connect blocks that are providing the current heat sinking path for the nuclear power plant. Directions of the connecting arrows represent the direction of heat flow along the current heat sinking path. If the current heat flow path of the plant changes, the connecting arrows are updated accordingly. Additional VDUs include: a mimic VDU displaying a mimic of a plant component; a procedures VDU displaying a stored procedure executable by the plant; a multi-trend VDU trending various plant data; and an alarms VDU displaying side-by-side alarms registries sorted by time and priority respectively. If a VDU fails, the displays are shifted to free up one VDU to present the display of the failed VDU, and one display is shifted to an additional VDU. | 11-07-2013 |
20130301772 | Risk Monitoring Device and Risk Monitoring Method for Use with a Nuclear Power Facility - The object of the present invention is to provide a risk monitoring device and a risk monitoring method for use with a nuclear power facility, providing continuous determination of risk associated with the nuclear power facility, based on one-type security model, which can be implemented using simple software and hardware means. The risk monitoring device according to the present invention comprises a memory device for storing at least one minimal fault cutset array (MFC) and probability values for each event in each MFC, and a data input device to input in the risk monitoring device data about status changes of the nuclear power facility facility, wherein the risk monitoring device further comprises a formation unit for forming at least one MFC matrix; a memory device for storing said at least one MFC matrix; a formation unit for forming at least one parameter matrix; a memory device for storing said at least one parameter matrix; a modification unit for modifying elements of said at least one parameter matrix; and a risk evaluation unit. | 11-14-2013 |
20130315362 | NUCLEAR DIGITAL INSTRUMENTATION AND CONTROL SYSTEM - A nuclear instrumentation and control system, comprising: an input module, receiving analog inputs from sensors and digital signals from hardware switches; a dual redundant bi-stable processor, connecting to the input module; a dual redundant local coincidence logic processor, connecting to the dual redundant b0-stable processor; an output module, connecting to the dual redundant local coincidence logic processor; an integrated communication processor, connecting to the dual redundant bi-stable processor and the dual redundant local coincidence logic processor; an interface and test panel, connecting to the dual redundant bi-stable processor, the dual redundant local coincidence logic processor and the integrated communication processor; and a video display unit, connecting to the dual redundant bi-stable processor, the dual redundant local coincidence logic processor, the integrated communication processor and the interface and test panel. Thereby, a qualification and certification tools for design and development of safety related equipment and explains the basis for many decisions made while performing the digital upgrade. | 11-28-2013 |
20150310945 | NUCLEAR REACTOR MONITORING DEVICE, NUCLEAR REACTOR CONTROL DEVICE, AND NUCLEAR POWER GENERATION PLANT - A nuclear reactor monitoring device, a nuclear reactor control device, and a nuclear power generation plant, wherein a detector ( | 10-29-2015 |
376217000 | Control programs | 19 |
20090080585 | Reduced Order Stress Model for Online Maneuvering, Diagnostics of Fuel Failure and Design of Core Loading Patterns of Light Water Reactors - The invention is principally directed to a reduced order model, XEDOR, facilitating the prediction of and the diagnostics of pellet-clad interaction stress-corrosion-cracking failure of nuclear fuel rods. The invention more particularly relates to assessment of susceptibility to PCI failure for guidance in the design of fuel loading in nuclear reactors. The invention additionally relates to the protection against PCI failure by providing operational information to operators of a nuclear reactor during power maneuvering, including predictive calculations prior to executing power maneuvers. Additionally, the invention relates to the diagnostics of an event suggesting a possible PCI cladding failure. | 03-26-2009 |
20100080334 | METHOD AND APPARATUS FOR VERIFYING PERFORMANCE OF CONTROL SYSTEM OF NUCLEAR POWER PLANT - Provided are a method and apparatus for validating dynamic performance of a control system of a nuclear power plant in operation, without performing a power ascension test. According to the present invention, when the performance of the control system requires to be validated in order to change a control logic or its setpoint of or to replace hardware of the control system, the dynamic performance of the control system may be validated without performing the power ascension test which can be performed only in a trial operation and requires large expenses. In the present invention, a design computer code capable of simulating a transient state of the nuclear power plant is connected to the hardware of the control system, and tests to be performed at the power ascension test or in the transient state of the nuclear power plant are simulated by directly using the hardware of the control system instead of a control system model of the design computer code, in an on-line state. | 04-01-2010 |
20100091928 | PROTECTION SYSTEMS FOR NUCLEAR BOILING WATER REACTORS - A protection system for a nuclear boiling water reactor may include a device configured to monitor reactor power; a device configured to monitor reactor pressure; a device configured to determine a power-dependent high reactor pressure setpoint, based on the monitored reactor power; and a device configured to initiate a protection system action when the monitored reactor pressure is greater than the power-dependent high reactor pressure setpoint. The power-dependent high reactor pressure setpoint that corresponds to at least one value of percent power in an operating domain of the reactor may be less than the power-dependent high reactor pressure setpoint that corresponds to 100% reactor power. | 04-15-2010 |
20110200155 | Nuclear Reactor System and Nuclear Reactor Control Method - In order to stably control a nuclear reactor in a short time, so as not to enter an unstable region that is determined by the relationship between the reactor pressure, the reactor power and the subcooling of the core inlet coolant at start-up time, the nuclear reactor system comprises: an power control apparatus for generating a control rod operation signal for operating a control rod, based on the reactor water temperature change rate; a feed water control apparatus for generating a feed water flow rate signal and a discharge water flow rate signals based on the reactor water level signal; and a process computer for performing overall control of the power control apparatus and the feed water control apparatus, wherein the feed water control apparatus has the reactor water temperature change rate setting section for adjusting the reactor water temperature change rate set value based on the variation of the reactor water level signal. | 08-18-2011 |
20110299646 | SYSTEM FOR SUPPORTING NUCLEAR POWER PLANT OPERATION - A system for supporting nuclear power plant operation includes an event data base that stores events corresponding to behaviors of the plant data. A countermeasure operation database stores operations corresponding to the events. An operation procedure database stores operation procedures that are required for the corresponding operations. An event discriminating section retrieves an event that occurs in a nuclear power plant from an event database so as to discriminate based on a behavior of plant data that is captured from the plant interface. A countermeasure retrieval section retrieves a countermeasure operation from the countermeasure operation database based on an event that is discriminated by the event discriminating section. A display control section displays an operation procedure that is required for performing the countermeasure operation on a display device. An operation confirmation section judges whether the countermeasure operation that is retrieved by the countermeasure retrieval section is completed. | 12-08-2011 |
20110311013 | SYSTEM AND APPARATUS FOR PLANT MONITORING AND CONTROL - A system and apparatus for monitoring and control of the operation of various types of industrial plants, including power plants, nuclear power plants and plants including various types of mechanical, electrical and chemical machinery. The invention employs modular non-microprocessor based, non-software based digital hardware that enables communication between sensors and control logic and between the control logic and actuators that control a functional aspect of each plant. | 12-22-2011 |
20120189087 | OSCILLATION POWER RANGE MONITOR AND METHOD OF CHECKING SOUNDNESS THEREOF - An oscillation power range monitor has: an input signal processing section that calculates a normalized cell value from LPRM signals input from local power range monitors; a soundness checking basic signal generating section that generates a simulated cell value that is variable on a time series basis; and a trip determining section that receives the normalized cell value and the simulated cell value respectively from the input signal processing section and the soundness checking basic signal generating section as input, compares the normalized cell value and the simulated cell value with a determination threshold value and outputs a scram trip signal when either of them exceeds the determination threshold value. | 07-26-2012 |
20130016802 | OSCILLATION POWER RANGE MONITOR AND METHOD OF CHECKING SOUNDNESS THEREOFAANM FURUSAWA; TakayoshiAACI TokyoAACO JPAAGP FURUSAWA; Takayoshi Tokyo JPAANM Umemura; NorihiroAACI TokyoAACO JPAAGP Umemura; Norihiro Tokyo JPAANM Miyazaki; TadashiAACI KanagawaAACO JPAAGP Miyazaki; Tadashi Kanagawa JP - An oscillation power range monitor has: an averaging section that assigns a plurality of LPRM readings input filtered to remove noise thereof from local power range monitors to calculate cell average value of the LPRM readings assigned to each cell; a time average processing section that calculates a cell time average value from the average value of each cell; a normalized cell value computing section that computes the normalized cell value for each cell from the cell time average value and the cell average value; a trip determining section that receives the normalized cell value, monitors oscillations of each cell output and outputs a scram trip when the normalized cell value exceeds a predetermined value; and an abnormality determining section that assigns a plurality of LPRM readings input and determines abnormality of each LPRM reading assigned to each cell based on the oscillations of the LPRM reading. | 01-17-2013 |
20130114776 | FAULT TOLERANT TURBINE SPEED CONTROL SYSTEM - A generator is installed on and provides electrical power from a turbine by converting the turbine's mechanical energy to electricity. The generated electrical power is used to power controls of the turbine so that the turbine can remain in use through its own energy. The turbine can be a safety-related turbine in a nuclear power plant, such that, through the generator, loss of plant power will not result in loss of use of the turbine and safety-related functions powered by the same. Appropriate circuitry and electrical connections condition the generator to work in tandem with any other power sources present, while providing electrical power with properties required to safely power the controls. | 05-09-2013 |
20130129028 | CONTROL SYSTEM FOR NUCLEAR FACILITIES - Provided are a safety protection system facility | 05-23-2013 |
20130148771 | MIXING SYSTEM - A mixing system including: a backup heater which increases an internal pressure of a pressurizer; a spray valve which decreases the internal pressure of the pressurizer; a pressure sensor which detects the pressure inside the pressurizer; and a pressure control unit which performs a feedback control on a spray valve so that the pressure becomes a target pressure based on a detection pressure value detected by the pressure sensor, wherein the pressure control unit includes a PID control unit which performs a feedback control when heating the coolant by the backup heater and outputs a pressure controller signal and a bias setting unit which sets a bias toward the operation side of the spray valve with respect to the pressure controller signal, and wherein the spray valve is operated based on the pressure controller signal subjected to the setting of the bias. | 06-13-2013 |
20130163709 | OPERATION MONITORING APPARATUS OF NUCLEAR POWER PLANT - An operation monitoring apparatus is provided with a function integration VDU ( | 06-27-2013 |
20130182809 | NUCLEAR POWER PLANT CONTROL SYSTEM AND NUCLEAR POWER PLANT CONTROL METHOD - A nuclear power plant control system ( | 07-18-2013 |
20130188765 | SYSTEM, METHOD, AND PROGRAM FOR MONITORING REACTOR CORE - According to one embodiment of a reactor core monitoring system, includes: an information retention portion for retaining a regular cycle and a short cycle as calculation information of reactor core performance data; a signal processing portion for creating heat balance data based on a process signal; a data acquisition portion for acquiring, in a timing of the regular cycle, the heat balance data and reactor core performance data which was calculated in a previous timing of the regular cycle, while acquiring, in a timing of the short cycle asynchronous to the regular cycle, the heat balance data and reactor core performance data which was calculated most recently; and a data calculation portion for calculating new reactor core performance data based on the acquired reactor core performance data and the heat balance data. | 07-25-2013 |
20130208844 | NUCLEAR REACTOR POWER MONITOR - Provide the technique for controlling nuclear power plant in which the thermal limit can be brought close to the full limit of operation restrictions by the automatic control, using the simple information outputted shorter cycle than that of the thermal limit. | 08-15-2013 |
20130294561 | REACTOR SHUTDOWN TRIP ALGORITHM - A controller for producing a nuclear reactor shutdown system trip signal in response to at least one detector signal. The controller includes a signal conditioning module receiving the at least one detector signal and outputting a measured flux signal. A rate module generates a rate signal from the measured flux signal. A comparator circuit compares the rate signal to a trip setpoint and generates a first trip signal. | 11-07-2013 |
20130294562 | REACTOR SHUTDOWN TRIP ALGORITHM - A controller for producing a nuclear reactor shutdown system trip signal in response to at least one detector signal. The controller includes a signal conditioning module receiving the at least one detector signal and outputting a measured flux signal. A rate module generates a rate signal from the measured flux signal. A comparator circuit compares the rate signal to a trip setpoint and generates a first trip signal. | 11-07-2013 |
20150049851 | CENTRAL CONTROL DEVICE OF NUCLEAR POWER PLANT, PLANT OPERATION SUPPORT DEVICE, AND PLANT OPERATION SUPPORT METHOD - A central control device of a nuclear power plant monitors and controls the nuclear power plant. The central control device includes monitoring operation devices (for example, an alarm VDU, a common system VDU, and a safety system VDU of an operation console) each having both a function as a display unit that displays information on the nuclear power plant (for example, operation information, safety information, and the like) and a function as an operation unit that operates the nuclear power plant, and a control unit that controls these monitoring operation devices. The control unit selects an operation procedure document corresponding to an input operation to a monitoring operation device and displays the operation procedure document on the monitoring operation device. | 02-19-2015 |
376218000 | Xenon control | 1 |
20100142666 | XENON OSCILLATION PREDICTION METHOD AND COMPUTER PROGRAM FOR XENON OSCILLATION PREDICTION - To predict xenon oscillation at the present time and later. For this purpose, as an axial offset of a power distribution of a reactor is represented by AOp, an axial offset of a power distribution based on xenon distribution is represented by AOx, and an axial offset of a power distribution based on an iodine distribution is represented by AOi, a parameter DAOpx(=AOp−AOx) and a parameter DAOix(=AOi−AOx) are described by a relational expression of a trigonometric function and an exponential function using an angular frequency of xenon oscillation. Next, phases with respect to initial values of the parameters DAOpx and DAOix are obtained (Step S | 06-10-2010 |