The present invention relates to a method for monitoring a nuclear power plant in a transient state, the method comprising the steps of: classifying signals to be monitored of the nuclear power plant into a constant monitoring signal, a primary system monitoring signal, a secondary system monitoring signal, and a monitoring signal during normal operation; constantly monitoring the constant monitoring signal at the time of starting the nuclear power plant; sequentially initiating monitoring of the primary system monitoring signal and the secondary system monitoring signal while monitoring the constant monitoring signal; and initiating monitoring of the monitoring signal during normal operation when it is determined to be operating normally after initiating the monitoring of the secondary system monitoring signal.

Systems and methods are described for providing power. A system comprising a generator, an inverter, and a battery can be used to provide power. The system can also comprise a transfer switch. The system can provide power to another device.

A safety method for a reactor including a primary circuit in which a water-based primary fluid is intended to circulate, and a secondary circuit, in which a water-based secondary fluid is intended to circulate, the secondary circuit being hydraulically isolated from the primary circuit and including a steam generator is provided. In the event of a meltdown of the core of the reactor with the formation of a corium bath in a bottom of the vessel: in response to the detection of the formation of a liquid metallic layer at the surface of the corium bath: the method provides for setting the secondary circuit in fluidic communication with the primary circuit so that the secondary fluid follows the primary circuit to flow inside the vessel over the liquid metallic layer of the corium bath.

A safety method for a reactor including a primary circuit and a secondary circuit fluidly isolated from the primary circuit, and a steam generator, and in the event of a meltdown of the core of the reactor with the formation of a corium bath in a bottom of the vessel and the formation of a liquid metallic layer at the surface of the corium bath, the method includes: a break-up by explosion of the fluidic insulation to set the secondary circuit in fluidic communication with the primary circuit so that the secondary fluid follows the primary circuit to flow inside the vessel over the liquid metallic layer of the corium bath.

An optical fiber penetration is disposed in a sleeve provided through a partition wall that separates a first space and a second space. The optical fiber penetration includes a first optical fiber cable and a second optical fiber cable each having a thin tube formed of metal and an optical fiber strand inserted in the thin tube, a cylindrical body that is formed of metal and is disposed in an axial direction of the sleeve, an interior of which includes the first optical fiber cable on a side of the first space and the second optical fiber cable on a side of the second space, an internal connector configured to connect the first optical fiber cable with the second optical fiber cable in the interior of the cylindrical body, and a first lid and a second lid configured to close one end and the other end of the cylindrical body.

An in-line dissolved gas removal membrane-based apparatus for removing dissolved hydrogen and fission gases from the letdown stream from a reactor coolant system.

A method, system, and apparatus for the thermal storage of energy generated by multiple nuclear reactor systems including diverting a first selected portion of energy from a portion of a first nuclear reactor system of a plurality of nuclear reactor systems to at least one auxiliary thermal reservoir, diverting at least one additional selected portion of energy from a portion of at least one additional nuclear reactor system of the plurality of nuclear reactor systems to the at least one auxiliary thermal reservoir, and supplying at least a portion of thermal energy from the auxiliary thermal reservoir to an energy conversion system of a nuclear reactor of the plurality of nuclear reactors.

A nuclear reactor includes an internal steam generator and a nuclear core disposed in a containment structure. A condenser is disposed outside the containment structure, and includes a condenser inlet line tapping off a steam line connected to the steam generator outside the containment structure, and a condensate injection line conveying condensate from the condenser to the integral steam generator. Isolation valves are located outside the containment structure on a feedwater line, the steam line, and the condensate injection line. The valves have an operating configuration in which the isolation valves on the feedwater and steam lines are open and the isolation valve on the condensate injection line is closed, and a heat removal configuration in which the isolation valves on the feedwater and steam lines are closed and the isolation valve on the condensate injection line is open.

Provided is a remotely operated manipulator which can be applied to a space which is wider on a back side than at an opening part, which has a simple structure, high stiffness, and high reliability. The remotely operated manipulator of the present invention includes: a circular base fixed to a wall surface; a beam which rotates on the circular base; a trolley which moves on the beam; and a mast which is raised and lowered with respect to the trolley and is mounted with a tool unit at a tip. Stiffness is improved by directly fixing the beam to the wall surface by a beam fixing device. Further, a work region is expanded by mounting a bending mast on the tip of the mast.

A device for removing shielding balls from calandria of a heavy water reactor is provided. The device includes a head for moving the shielding balls positioned inside of an end shield of the calandria to an outside of the end shield; and a mover for moving the head to the end shield of the calandria. The head includes a head body, an opening former installed on the head body and configured to form an opening in the end shield, and a gate installed on the head body and configured to control an amount of the shielding balls discharged to the outside through the opening.