A detector signal-processing circuit comprises the following: a current/voltage conversion part that converts the current value of a neutron detector to a voltage value; a variable gain amplification part that performs amplification by a first-step variable gain using a D/A converter; a current level response-use resistance circuit that selects the measurement range in accordance with the voltage value; temperature measurement units for measuring the temperature of the resistance circuit for current level response; a temperature compensation part for commanding gain compensation by the D/A converter on the basis of the measured temperature; and a selective adjustment control part for selective control of the measurement range and adjustment of the variable gain of the variable gain amplification part. Due to this configuration, neutron flux can be measured with high precision while maintaining a constant output precision, before and after switching of the measurement range.

A method is for controlling a nuclear power plant comprising pressurized water nuclear reactor (3) having a reactor core producing power, a primary circuit (5) connecting the reactor core to a steam generator (9), one or more of control rods (16), which can be moved into the reactor core for controlling the power of the reactor core, an injecting device (22, 23, 24, 26, 28, 30) for injecting boric acid and/or deionized water into the primary circuit (5) for controlling the reactivity of the reactor core.

A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

A method for determining at least one threshold value of at least one operating parameter of a nuclear reactor is implemented by an electronic determination system and includes the steps of determining a first threshold value of a respective operating parameter for an operation of the reactor at a first power; and determining a second threshold value of said parameter for an operation of the reactor at a second power. The operation at the lower power of the first and second powers is an operation continued for a duration of at least 8 hours over a 24-hour sliding window. The method also includes determining a third threshold value of said parameter for an operation of the reactor at a third power between the first power and the second power.

A method for determining at least one threshold value of at least one operating parameter of a nuclear reactor is implemented by an electronic determination system and includes the steps of determining a first threshold value of a respective operating parameter for an operation of the reactor at a first power; and determining a second threshold value of said parameter for an operation of the reactor at a second power. The operation at the lower power of the first and second powers is an operation continued for a duration of at least 8 hours over a 24-hour sliding window. The method also includes determining a third threshold value of said parameter for an operation of the reactor at a third power between the first power and the second power.

A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

A method regulates operating parameters comprising at least the mean temperature of the core (T.sub.m), and the axial power (AO) imbalance. The method includes development of a vector (U.sub.S) of control values of the nuclear reactor by a supervisor (31) implementing a predictive control algorithm; development of a vector (u.sub.K) of corrective values of the nuclear reactor controls by a regulator (33) implementing a sequenced gain control algorithm; development of a vector (U) of corrected values of the commands of the nuclear reactor, by using the vector (U.sub.S) of the values of the commands produced by the supervisor (31) and the vector (u.sub.K) of the corrective values of the commands produced by the regulator (33); and regulation of the operating parameters of the nuclear reactor, by controlling actuators using the vector (U) of the corrected values of the controls.

A method regulates operating parameters comprising at least the mean temperature of the core (T.sub.m), and the axial power (AO) imbalance. The method includes development of a vector (U.sub.S) of control values of the nuclear reactor by a supervisor (31) implementing a predictive control algorithm; development of a vector (u.sub.K) of corrective values of the nuclear reactor controls by a regulator (33) implementing a sequenced gain control algorithm; development of a vector (U) of corrected values of the commands of the nuclear reactor, by using the vector (U.sub.S) of the values of the commands produced by the supervisor (31) and the vector (u.sub.K) of the corrective values of the commands produced by the regulator (33); and regulation of the operating parameters of the nuclear reactor, by controlling actuators using the vector (U) of the corrected values of the controls.