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US 4,400,343 AGranted
System and method for controlling operation of boiling water reactor
AssigneeHitachi, Ltd.
InventorsMasayuki Izumi, Renzo Takeda
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AssigneeHitachi, Ltd.
InventorsMasayuki Izumi, Renzo Takeda
Estimating the term…
The pressure P.sub.R in the reactor pressure vessel, the flow rate W.sub.c of the cooling water flowing through the core in the reactor pressure vessel, and the flow rate W.sub.STM of the steam supplied from the reactor pressure vessel to the turbine are detected. The enthalpy H.sub.f of the saturated cooling water is determined on the basis of the pressure P.sub.R. The values of the cooling water flow rate W.sub.c, the steam flow rate W.sub.STM, the enthalpy H.sub.f of the saturated cooling water and a predetermined enthalpy H.sub.IN of the cooling water at the core inlet are substituted into the equation below thereby to obtain the enthalpy H.sub.fw of the feed water. ##EQU1## An error is determined between the feed-water enthalpy H.sub.fw thus obtained and the enthalpy T.sub.fw of the feed water actually supplied into the reactor pressure vessel, and on the basis of this error, the opening of the flow rate control valve on the turbine bleeding pipe is adjusted, so that the flow rate of the steam bled from the turbine for heating the feed water is adjusted according to the error.
A system for controlling the operation of a boiling water reactor, comprising first detector means for detecting the pressure in the reactor vessel, second detector means for detecting the flow rate of the cooling water flowing in the core in the reactor vessel, third detector means for detecting the flow rate of the steam supplied to a turbine from said reactor vessel, means for setting the enthalpy of said cooling water at the inlet of said core at a value in dependence on the reactor power, said set value rendering the void fraction in the lower part of the core when the reactor power is less than a predetermined maximum value to be greater than the void fraction in the lower part of the core when the reactor power is at the predetermined maximum value so as to flatten the power distribution in the axial direction of the core when the reactor power is less than the predetermined maximum value, means for adjusting the enthalpy of the feed water supplied to said reactor vessel, and means for controlling said feed water enthalpy adjusting means on the basis of said pressure, said cooling water flow rate and said steam flow rate detected by said first, second and third detector means respectively and said cooling water enthalpy set by said setting means, thereby effecting a start-up of the reactor.
A system for controlling the operation of the boiling water reactor, comprising a reactor vessel, a turbine supplied with the steam produced by said reactor vessel, means for supplying the feed water to said reactor vessel, means for heating said feed water to control the void fraction in the lower part of the core so as to flatten the power distribution in the axial direction of the core, and means for controlling the amount of heat supplied from said feed water heating means to said feed water, said heat amount control means reducing the amount of heat applied to said feed water according as the reactor power increases from a first level up to a second predetermined maximum level to flatten the power distribution in the axial direction of the core.
A method of controlling the operation of the boiling water reactor, comprising:
A method of controlling the operation of a boiling water reactor for effecting a rapid start-up of the reactor, comprising the steps of:
A system for controlling the operation of a nuclear reactor having a reactor vessel and a core, comprising first detector means for detecting the pressure in the reactor vessel and for providing a first output signal indicative thereof, second detector means for detecting the flow rate of cooling water flowing in the core of the reactor vessel and for providing a second output signal indicative thereof, third detector means for detecting the flow rate of steam supplied from the reactor vessel to a turbine and for providing a third output signal indicative thereof, means for setting a value of the enthalpy of the cooling water at the inlet of said core in dependence on reactor power and for providing a set output signal indicative thereof, said set value rendering the void fraction in the lower part of the core when the reactor power is less than a predetermined maximum value to be greater than the void fraction in the lower part of the core when the reactor power is at the predetermined maximum value so as to flatten the power distribution in the axial direction of the core when the reactor power is less than the predetermined maximum value, means for adjusting the enthalpy of the feed water supplied to the reactor vessel, and means for controlling the feed water enthalpy adjusting means in response to the set output signal and said first, second and third output signals.
Dependencies are inferred from the claim text.