Power conditioning device for nuclear reactors

Purpose: To suppress the pressure increase upon ATWS. Constitution: Main steam separation valves are disposed to main steam pipe lines and a closure signal outputted from a main steam separation valve closure detector upon closure of the main steam separation valves is applied to a solenoid interrupter. When the solenoid interrupter is actuated, a recycling pump is tripped to reduce the flow rate of coolants introduced by way of a jet pump to a reactor core, in which only the coolants by the spontaneous circulation are supplied to the reactor core. Accordingly, the reactor power is reduced and the pressure in the reactor is decreased. (Seki, T.)