Abstract: 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.

Abstract: A nuclear power plant control system including: a detection unit for detecting a specific event occurring in the nuclear power plant; an on-site equipment handling the event; and a majority decision judging device and an on-site equipment control device which constitute a plurality of control devices respectively operating independently. Each of the control devices includes a plurality of arithmetic units which perform arithmetic processes independently and in parallel based on a detection result of the detection unit, and output a signal for controlling the on-site equipment according to the results of operations of the arithmetic processes. The plurality of arithmetic units perform a matching process for harmonizing process statuses of the arithmetic processes of respective arithmetic units with each other when starting up the control devices, and after completing the matching process, respectively perform the arithmetic processes independently and in parallel.

Abstract: A nuclear power plant control system (1) includes a control button (21) which receives an operation for controlling a control target device (40), a notification lamp (12) which notifies that a control signal corresponding to the operation received by the control button (21) arrives at a predetermined position on a path connected from a control panel (20) to the control target device (40), and a control signal inhibition unit (33) which inhibits a control signal from arriving at the control target device (40) in midstream between the predetermined position on the path and the control target device (40) in response to an operation received by a test permission button (11).

Abstract: A nuclear power control system includes: a safety protection apparatus which outputs a first safety mode operating signal while outputting a first unsafety mode operating signal; a CCF apparatus that outputs a second safety mode operating signal; and a signal input/output circuit that is connected to the safety protection apparatus and the CCF apparatus. The signal input/output circuit includes an OR circuit that outputs a third safety mode operating signal based on the presence or absence of an input of the first safety mode operating signal and the second safety mode operating signal; a NOT circuit that is connected to the output side of the OR circuit; and an AND circuit that outputs a third unsafety mode operating signal, and the presence and absence of an input of a first unsafety mode operating signal.

Abstract: A reactor shutdown system includes a reactor, a control-rod drive unit that can drive a control rod in pulling and inserting directions with respect to a fuel assembly, a power source that can supply power to the control-rod drive unit, and a power converter that is provided between the control-rod drive unit and the power source, in which when power supply is cut off, the control-rod drive unit inserts the control rod into the fuel assembly to stop nuclear reaction in the reactor, and the reactor shutdown system includes a reactor trip breaker provided between the power converter and the control-rod drive unit, a safety protection-system device that controls the reactor trip breaker to cut off power supply to the control-rod drive unit, and a CCF device that controls the power converter to cut off power supply to the control-rod drive unit.

Abstract: A nuclear power plant control system (1) includes a control button (21) which receives an operation for controlling a control target device (40), a notification lamp (12) which notifies that a control signal corresponding to the operation received by the control button (21) arrives at a predetermined position on a path connected from a control panel (20) to the control target device (40), and a control signal inhibition unit (33) which inhibits a control signal from arriving at the control target device (40) in midstream between the predetermined position on the path and the control target device (40) in response to an operation received by a test permission button (11).

Abstract: A nuclear power control system includes: a safety protection apparatus which outputs a first safety mode operating signal while outputting a first unsafety mode operating signal; a CCF apparatus that outputs a second safety mode operating signal; and a signal input/output circuit that is connected to the safety protection apparatus and the CCF apparatus. The signal input/output circuit includes an OR circuit that outputs a third safety mode operating signal based on the presence or absence of an input of the first safety mode operating signal and the second safety mode operating signal; a NOT circuit that is connected to the output side of the OR circuit; and an AND circuit that outputs a third unsafety mode operating signal, and the presence and absence of an input of a first unsafety mode operating signal.

Abstract: 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.

Abstract: A nuclear power plant control system including: a detection unit for detecting a specific event occurring in the nuclear power plant; an on-site equipment handling the event; and a majority decision judging device and an on-site equipment control device which constitute a plurality of control devices respectively operating independently. Each control devices includes a plurality of arithmetic units which perform arithmetic processes independently and in parallel based on a detection result of the detection unit, and output a signal for controlling the on-site equipment according to the results of operations of the arithmetic processes. The plurality of arithmetic units perform a matching process for harmonizing process statuses of the arithmetic processes of respective arithmetic units with each other when starting up the control devices, and after completing the matching process, respectively perform the arithmetic processes independently and in parallel.

Abstract: A nuclear power plant control system includes control devices, and the control devices 30a and 30b each include arithmetic units that respectively execute arithmetic processing in parallel independently, based on detection results of detection units, and each output a control signal to control a countermeasure unit in accordance with an arithmetic result of the arithmetic processing, a transmission unit that sends out the control signal to the countermeasure unit, when the control signal is outputted from at least one of the arithmetic units, and a system management unit that performs control so as to inhibit the control signal outputted by the arithmetic unit as a test object from being sent out from the transmission unit while maintaining a state where the other arithmetic operation executes the arithmetic processing independently, when a test of either of the control devices is conducted.

Abstract: An operation monitoring apparatus is provided with a function integration VDU (21) including a normal use system VDU (32) which operates and monitors a nuclear power plant under a normal state, and a safety protection system VDU (31) which shuts down the nuclear power plant under an abnormal state, and also a safety protection system VDU (22) which shuts down the nuclear power plant under the abnormal state, and further, a block device which inhibits an actuation of the safety protection system VDU (31) when the function integration VDU (21) is under an abnormal state, thereby capable of simplifying an operation manipulation in the nuclear power plant, and ensuring a high level of safety of an operation control.

Abstract: A rector shutdown system includes a reactor, a control-rod drive unit that can drive a control rod in pulling and inserting directions with respect to a fuel assembly, a power source that can supply power to the control-rod drive unit, and a power converter that is provided between the control-rod drive unit and the power source, in which when power supply is cut off, the control-rod drive unit inserts the control rod into the fuel assembly to stop nuclear reaction in the reactor, and the rector shutdown system includes a reactor trip breaker provided between the power converter and the control-rod drive unit, a safety protection-system device that controls the reactor trip breaker to cut off power supply to the control-rod drive unit, and a CCF device that controls the power converter to cut off power supply to the control-rod drive unit.