Control device, control method, and program for controlling continuous casting process

Patent metadata

Field	Value
Publication number	US-11344946-B2
Application number	US-201917256778-A
Country	US
Kind code	B2
Filing date	Sep 17, 2019
Priority date	Sep 18, 2018
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

A control device for continuous casting continuously producing a slab by injecting a molten metal from a nozzle to a mold and extracting the molten metal while solidifying the molten metal, includes a molten metal level meter measuring a molten metal level in the mold, a main control unit obtaining an operation amount of a flow rate adjusting mechanism that adjusts a flow rate of a molten metal injected to the mold from the nozzle such that a molten metal level measured by the molten metal level meter follows a molten metal level target value, a flowmeter measuring the flow rate of the molten metal injected to the mold from the nozzle, an input disturbance correction unit obtaining a first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control unit.

First claim

What is claimed is:

1. A control device for a continuous casting process which is configured to continuously produce a slab by injecting a molten metal from a nozzle to a mold and extracting the molten metal while solidifying the molten metal, the control device comprising:
a molten metal level meter that is configured to measure a molten metal level in the mold,
a main control unit that is configured to obtain an operation amount of a flow rate adjusting mechanism that adjusts a flow rate of the molten metal injected to the mold from the nozzle such that the molten metal level measured by the molten metal level meter follows a molten metal level target value,
a flowmeter that is configured to measure the flow rate of the molten metal injected to the mold from the nozzle,
an input disturbance correction unit that is configured to obtain a first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control unit, in accordance with an input disturbance estimation value obtained according to a flow rate measurement value of the molten metal measured by the flowmeter, and
an extraction disturbance correction unit that is configured to obtain a second correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control unit, in accordance with an extraction disturbance estimation value obtained according to a molten metal level measurement value measured by the molten metal level meter.

2. The control device for a continuous casting process according to claim 1 , further comprising:
a flow rate estimation unit that is configured to calculate a flow rate estimation value of a molten metal associated with an opening degree using a flow rate characteristic model indicating a relationship between the operation amount of the flow rate adjusting mechanism and the flow rate of the molten metal,
wherein the input disturbance correction unit is configured to use a difference between the flow rate measurement value of the molten metal measured by the flowmeter and a flow rate estimation value of the molten metal calculated by the flow rate estimation unit as the input disturbance estimation value, and obtain the first correction amount according to the input disturbance estimation value.

3. The control device for a continuous casting process according to claim 2 ,
wherein the input disturbance correction unit is configured to obtain the first correction amount by using an inverse model of the flow rate characteristic model.

4. The control device for a continuous casting process according to claim 2 ,
wherein the extraction disturbance correction unit is configured to obtain the second correction amount by using an inverse model of the flow rate characteristic model.

5. The control device for a continuous casting process according to claim 1 , comprising an extraction disturbance estimation unit that is configured to obtain the extraction disturbance estimation value by configuring a state observer in which the molten metal level and an extraction disturbance are state variables, using a process model indicating a response to the molten metal level with respect to a flow rate of the molten metal, using the flow rate measurement value of the molten metal measured by the flowmeter and the molten metal level measurement value measured by the molten metal level meter as inputs,
wherein the extraction disturbance correction unit is configured to obtain the second correction amount in accordance with the extraction disturbance estimation value obtained by the extraction disturbance estimation unit.

6. The control device for a continuous casting process according to claim 5 , wherein the state observer is a Luenberger observer.

7. The control device for a continuous casting process according to claim 1 ,
wherein the flowmeter is an electromagnetic flowmeter.

8. A control method for a continuous casting process of continuously producing a slab by injecting a molten metal from a nozzle to a mold and extracting the molten metal while solidifying the molten metal, the control method comprising:
a molten metal level measuring process of measuring a molten metal level in the mold by using a molten metal level meter,
a main control process of obtaining an operation amount of a flow rate adjusting mechanism that adjusts a flow rate of a molten metal injected to the mold from the nozzle such that the molten metal level measured in the molten metal level measuring process follows a molten metal level target value,
a flow rate measuring process of measuring the flow rate of the molten metal injected to the mold from the nozzle by a flowmeter,
an input disturbance correcting process of obtaining a first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control process, in accordance with an input disturbance estimation value obtained according to the flow rate measurement value of the molten metal measured in the flow rate measuring process, and
an extraction disturbance correcting process of obtaining a second correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control process, in accordance with an extraction disturbance estimation value obtained according to a molten metal level measurement value measured by the molten metal level meter.

9. A non-transitory computer readable storage medium encoded with computer readable instructions, which, when executed by processor circuitry, causes the processor circuitry to perform a method for controlling a continuous casting process of continuously producing a slab by injecting a molten metal from a nozzle to a mold and extracting the molten metal while solidifying the molten metal, the method comprising:
a main control process of obtaining an operation amount of a flow rate adjusting mechanism that adjusts a flow rate of the molten metal injected to the mold from the nozzle such that a molten metal level measured by a molten metal level meter follows a molten metal level target value,
an input disturbance correcting process of obtaining a first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control process, in accordance with an input disturbance estimation value obtained according to the flow rate measurement value of the molten metal measured by the flowmeter, and
an extraction disturbance correcting process of obtaining a second correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control process, in accordance with an extraction disturbance estimation value obtained according to a molten metal level measurement value measured by the molten metal level meter.

Assignees

• Nippon Steel Corp

Inventors

• Yamamoto Hiroki

Classifications

• B22D11/186 Primary

  by using electric, magnetic, sonic or ultrasonic means · CPC title

• B22D11/16

  Controlling or regulating processes or operations · CPC title

• B22D46/00

  Controlling, supervising, not restricted to casting covered by a single main group, e.g. for safety reasons (controlling or regulating in general G05) · CPC title

• B22D11/18

  for pouring (B22D11/20 takes precedence) · CPC title

• B22D11/181 Primary

  responsive to molten metal level or slag level · CPC title