306results about "Plant parameters regulation" patented technology

A method of calibrating excore detectors for a pressurized water reactor (PWR) (1) includes: measuring peripheral core flux signals using excore detectors (33) disposed at a plurality of locations spaced about the periphery of the core (9), and using the measured power distribution from either a core monitoring system (43) or in-core flux measurement (69). Calibration of the excore detectors (33) 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 (83) nodal calibration factors, which represent the ratio of the measured three-dimensional power distribution (75) 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 (9).

A feedwater control system considering a pressure drop of feedwater control valve in a nuclear power plant and a control method therefor are provided. In the feedwater control system, a first detection unit includes: a flow error signal generator for generating a flow error signal corresponding to a difference between a steam flow signal and a feedwater flow signal; and a water level correction error signal generator for generating a water level correction error signal corresponding to a sum of a water level measurement signal and the flow error signal. A second detection unit includes: a pressure drop sensor unit for detecting a pressure difference between front and rear portions of at least one feedwater control valve among the main feedwater control valves and the downcorner feedwater control valves and generating a pressure drop signal corresponding to the detected pressure difference; a pressure drop setup value signal generator for generating a pressure drop setup value signal corresponding to a previously set pressure drop setup value of the feedwater control valves; and a pressure drop error signal generator for comparing the pressure drop signal with the pressure drop setup value signal and generating a pressure drop error signal. A control unit controls the main feedwater pump based on a correction control signal output from the correction control signal generator.

Methods for evaluating robustness of solutions to constraint problems include: (a) determining one or more inputs for the constraint problem; (b) determining bias, uncertainty, or bias and uncertainty of the one or more inputs; (c) randomly perturbating at least one of the one or more inputs based on the bias, uncertainty, or bias and uncertainty of the one or more inputs to determine one or more modified inputs; (d) generating a solution to the constraint problem based on the one or more modified inputs; (e) storing the solution; (f) repeating (c) through (e) until multiple solutions are stored; and / or (g) determining the robustness of the stored multiple solutions by comparison of the stored multiple solutions to each other. The one or more modified inputs include the randomly perturbated input or inputs and / or the non-perturbated input or inputs.

A method is provided for determining and controlling feed water level in a steam generator of a nuclear power plant, whereby the water level sensor is calibrated in terms of the pressure drop across structural components in the feed water path. The water level differential pressure sensor is calibrated so that maximum water level is indicated as the level corresponding to the upper tap level plus the pressure drop across the foregoing structural components at maximum power plant power.