Control rod drives include all-digital monitoring, powering, and controlling systems for operating the drives. Each controlling system includes distinct microprocessor-driven channels that independently monitor and handle control rod drive position information reported from multiple position sensors per drive. Controlling systems function as rod control and information systems with top-level hardware interfaced with nuclear plant operators other plant systems. The top-level hardware can receive operator instructions and report control rod position, as well as report errors detected using redundant data from the multiple sensors. Positional data received from each drive is multiplexed across plural, redundant channels to allow verification of the system using independent position data as well as operation of the system should a single channel or detector fail. Control rod drives are capable of positioning and detecting position of control elements in fine increments, such as 3-millimeter increments, with plural position sensors that digitally report drive status and position.

Control rod drives include all-digital monitoring, powering, and controlling systems for operating the drives. Each controlling system includes distinct microprocessor-driven channels that independently monitor and handle control rod drive position information reported from multiple position sensors per drive. Controlling systems function as rod control and information systems with top-level hardware interfaced with nuclear plant operators other plant systems. The top-level hardware can receive operator instructions and report control rod position, as well as report errors detected using redundant data from the multiple sensors. Positional data received from each drive is multiplexed across plural, redundant channels to allow verification of the system using independent position data as well as operation of the system should a single channel or detector fail. Control rod drives are capable of positioning and detecting position of control elements in fine increments, such as 3-millimeter increments, with plural position sensors that digitally report drive status and position.

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 (Us) 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 (Us) 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.

Control rod drives include all-digital monitoring, powering, and controlling systems for operating the drives. Each controlling system includes distinct microprocessor-driven channels that independently monitor and handle control rod drive position information reported from multiple position sensors per drive. Controlling systems function as rod control and information systems with top-level hardware interfaced with nuclear plant operators other plant systems. The top-level hardware can receive operator instructions and report control rod position, as well as report errors detected using redundant data from the multiple sensors. Positional data received from each drive is multiplexed across plural, redundant channels to allow verification of the system using independent position data as well as operation of the system should a single channel or detector fail. Control rod drives are capable of positioning and detecting position of control elements in fine increments, such as 3-millimeter increments, with plural position sensors that digitally report drive status and position.

Control rod drives include all-digital monitoring, powering, and controlling systems for operating the drives. Each controlling system includes distinct microprocessor-driven channels that independently monitor and handle control rod drive position information reported from multiple position sensors per drive. Controlling systems function as rod control and information systems with top-level hardware interfaced with nuclear plant operators other plant systems. The top-level hardware can receive operator instructions and report control rod position, as well as report errors detected using redundant data from the multiple sensors. Positional data received from each drive is multiplexed across plural, redundant channels to allow verification of the system using independent position data as well as operation of the system should a single channel or detector fail. Control rod drives are capable of positioning and detecting position of control elements in fine increments, such as 3-millimeter increments, with plural position sensors that digitally report drive status and position.

A nuclear reactor protection system includes a plurality of functionally independent modules, each of the modules configured to receive a plurality of inputs from a nuclear reactor safety system, and logically determine a safety action based at least in part on the plurality of inputs, each of the functionally independent modules comprising a digital module or a combination digital and analog module, an analog module electrically coupled to one or more of the functionally independent modules, and one or more nuclear reactor safety actuators communicably coupled to the plurality of functionally independent modules to receive the safety action determination based at least in part on the plurality of inputs.

A nuclear reactor protection system includes a plurality of functionally independent modules, each of the modules configured to receive a plurality of inputs from a nuclear reactor safety system, and logically determine a safety action based at least in part on the plurality of inputs, each of the functionally independent modules comprising a digital module or a combination digital and analog module, an analog module electrically coupled to one or more of the functionally independent modules, and one or more nuclear reactor safety actuators communicably coupled to the plurality of functionally independent modules to receive the safety action determination based at least in part on the plurality of inputs.

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 B.sub.A/A.sub.A, C.sub.A/A.sub.A, and D.sub.A/A.sub.A) 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.

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 B.sub.A/A.sub.A, C.sub.A/A.sub.A, and D.sub.A/A.sub.A) 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.