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US 12,638,171 B2Granted
Integrated control logic device and operating method thereof to control water level of steam generator of nuclear power plant
AssigneeKepco Engineering & Construction Company, Inc.
InventorsSee Chae Jeong, In Ho Song, Myung Jun Song, Jae Young Huh, Gyu Cheon Lee
Life of this patent
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Abstract
An integrated control logic device and an operating method thereof adjust a position of a main control valve and a position of an auxiliary control valve. In particular, the position of the auxiliary control valve is adjusted by determining whether a change in the position of the main control valve is in a preset deadband range, thereby preventing a periodic water level fluctuation of a steam generator of a nuclear power plant.
Claims5
An integrated control logic device for a main control valve and an auxiliary control valve to control a water level of a steam generator of a nuclear power plant,
- a feedwater flow rate adjustment capacity of the main control valve being greater than that of the auxiliary control valve,
- the integrated control logic device comprising at least one processor including a plurality of functional units including:
- input signal processing unit configured to receive a steam generator water level value, feedwater flow rate value, steam flow rate value, and a nuclear reactor power value;
- a water level setpoint value processing unit configured to calculate a water level setpoint value based on the nuclear reactor power value;
- a proportional-integral type control unit configured to generate a main control value using the steam generator water level value, the feedwater flow rate value, the steam flow rate value, and the water level setpoint value;
- an auxiliary control valve opening determination unit configured to determine a first auxiliary control valve opening demand value based on the main control value;
- a main control valve opening determination unit configured to calculate a first main control valve opening demand value based on the main control value;
- a main control valve hysteresis function unit configured to
- calculate a second main control valve opening demand value on the basis of a main control valve deadband setpoint value and the first main control valve opening demand value, and
- adjust opening degree of the main control valve according to the second main control valve opening demand value;
- an auxiliary control valve opening compensation unit configured to calculate an auxiliary control valve opening compensation value on the basis of a difference between the first main control valve opening demand value and the second main control valve opening demand value;
- and
- an auxiliary control valve opening demand selection unit configured to
- calculate a second auxiliary control valve opening demand value on the basis of the first auxiliary control valve opening demand value and the auxiliary control valve opening compensation value, and
- adjust opening degree of the auxiliary control valve according to the second auxiliary control valve opening demand value,
- wherein the main control valve hysteresis function unit is further configured to:
- set the main control valve deadband setpoint value based on a maximum value of a valve opening range where a stiction of the main control valve occurs,
- determine a deadband range based on the main control valve deadband setpoint value,
- when the first main control valve opening demand value changes within the deadband range,
- maintain the second main control valve opening demand value, and
- when the first main control valve opening demand value changes beyond the deadband range,
- change the second main control valve opening demand value as the changed first main control valve opening demand value.
19 more elements
A method of operating an integrated control logic device for a main control valve and an auxiliary control valve to control a water level of a steam generator of a nuclear power plant,
- a feedwater flow rate adjustment capacity of the main control valve being greater than that of the auxiliary control valve,
- the integrated control logic device comprising at least one processor including a plurality of functional units including
- an input signal processing unit,
- a water level setpoint value processing unit,
- a proportional-integral type control unit,
- an auxiliary control valve opening determination unit,
- a main control valve opening determination unit,
- a main control valve hysteresis function unit,
- an auxiliary control valve opening compensation unit, and
- an auxiliary control valve opening demand selection unit,
- the operating method comprising:
- receiving, by the input signal processing unit, a steam generator water level value, a feedwater flow rate value, a steam flow rate value, and a nuclear reactor power value;
- calculating, by the water level setpoint value processing unit, a water level setpoint value based on the nuclear reactor power value;
- generating, by the proportional-integral type control unit, a main control value using the steam generator water level value, the feedwater flow rate value, the steam flow rate value, and the water level setpoint value;
- determining, by the auxiliary control valve opening determination unit, a first auxiliary control valve opening demand value based on the main control value;
- determining, by the main control valve opening determination unit, a first main control valve opening demand value based on the main control value;
- calculating, by the main control valve hysteresis function unit, a second main control valve opening demand value on the basis of a main control valve deadband setpoint value and the first main control valve opening demand value,
- and adjusting opening degree of the main control valve according to the second main control valve opening demand value;
- calculating, by the auxiliary control valve opening compensation unit, an auxiliary control valve opening compensation value based on a difference between the first main control valve opening demand value and the second main control valve opening demand value;
- and
- calculating, by the auxiliary control valve opening demand selection unit, a second auxiliary control valve opening demand value on the basis of the first auxiliary control valve opening demand value and the auxiliary control valve opening compensation value,
- and adjusting opening degree of the auxiliary control valve according to the second auxiliary control valve opening demand value;
- wherein the calculating of the second main control valve opening demand value comprises:
- setting the main control valve deadband setpoint value based on a maximum value of a valve opening range where a stiction of the main control valve occurs,
- determining a deadband range based on the main control valve deadband setpoint value,
- when the first main control valve opening demand value changes within the deadband range,
- maintaining the second main control valve opening demand value, and
- when the first main control valve opening demand value changes beyond the deadband range,
- changing the second main control valve opening demand value as the changed first main control valve opening demand value.
26 more elements
Dependencies are inferred from the claim text.