• Journal of Institute of Control, Robotics and Systems
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• v.6 no.9
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• pp.822-830
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• 2000

A conventional advanced control algorithm is proposed in this paper for improved temperature regulation of a TV-glass melting furnace. The TV-Glass melting furnace is a typical MIMO(Multi-Input Multi Output) system which is subject to various thermal disturbances. Because of its complexity, a detailed mathematical model of the furnace is hard to establish. To design a temperature control control system of the furnace, major input-output variables are selected first, and simple FOPDT(First Order Plus Dead Time) models are established based on the physical meaning and experimental process data. Based on the FOPDT models, a multi-loop control system composed of cascade and single loops are designed for effective control of the MIMO system. Practical implementation on the 150 ton/day furnace using the DCS(Distributed Control System) showed that the proposed control technique performs better than manual control.

• Journal of the Korean Society of Systems Engineering
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• v.12 no.1
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• pp.113-120
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• 2016

Steel in a continuous reheat furnace is heated to higher temperature to be treated in the rolling steel process. Due to this reason the continuous reheat furnace system requires an optimal control system to adjust the temperature inside the furnace. Level 2 control systems for continuous reheat furnaces generate automatic heating set points for the level 1 system of the furnace based on the mathematical thermal model which can give a good estimation of steel heating inside the furnace and is used to adjust heating requirements to optimize furnace combustion. For the current study the analytic methodology based on the design procedure from the systems engineering to develop new level 2 control system of a continuous reheat furnace was proposed. The system analysis and the requirements of the level 2 control system were derived using the unified modeling language (UML) 2.0, and the design of database and the graphic user interface (GUI) for the level 2 control system were conducted.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.840-843
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• 1997

We applied a DCS which was developed in Korea to test furnace. Test furnace is a pilot-scale plant made for finding combustion in firing coal. In this paper, we describe control system which was implemented in test furnace in detail. Finally, we describe the fire box temperature control loop, and show fire box temperature control result during commissioning stage using implemented control system.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.115-120
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• 1993

It is difficult to establish a mathematical furnace model and automatic-fumace control because of the difficulty in direct measurement of the inner condition of a blast furnace. To solve this problem, we has developed and actually operated a blast furnace operation control system using artificial intelligence tool to be applied to the blast furnace process computer system. Since this system has a function of automatic Treat level control, higher practicality has been proved than the previous guidance-level expert system. This paper introduces an outline of the system and the result of application.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.3
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• pp.311-318
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• 1997

In this paper, a controller with monitoring functions is proposed for controlling temperature of an electric furnace system. The controller includes holding and ramp control functions, and the control program for the temperature process monitor of the electric furnace. For this purpose, the implementation and performance of auto tuning algorithms in a computer¬based controller is studied in relation to control of a nonlinear electric furnace system which is characterized with large time delay. The communicator of a control and detection signals, between the controller and the electric furnace is implemented by an I/O data card. Experiments for the practical electric furnace are performed to illustrate the performance of the proposed controller.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.80-86
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• 1997

In this paper, a temperature controller with monitor function is proposed for the electric furnace system. This controller includes holding and ramp control function, and the control program for the temperature process monitor of the electric furnace. For this purpose, the implementation and performance of auto tuning algorithms in a computer-based controller was studied in relation to the control of nonlinear electric furnace system which is characterized with large delay time. The control program for this controller programmed by c-language. To communicate a control and detection signals, between the controller and the electric furnace is implemented by the I/O data card. We apply the temperature controller to the practical electric furnace. As a result, the proposed controller shows the better status characteristic.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.538-541
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• 1995

In steel works, reheating furnace is an essential part of a rod mill plant and it treats various types of billets continuously. Although getting an optimal setting for a single billet is simple, control setting for whole groups of billets is a difficult task. In this work, we studied a detail mathematical model and optimal control setting of reheating furnace. As the mathematical model of each billet is a partial differential equation, on-line control is almost impossible for the whole billets charged into the furnace. Therefore, we tried to provide a guideline for optimal setting value of the roof(index) temperature for the target billets which account for about 20% of the charged billets.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.22-25
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• 1995

This paper shows adaptive control using RHPC(Receding Horizon Predictive Control) with equality constraint which applied to Electric Furnace. The control strategy includes monotonic weighting (improving transient response) and pre-filtering (enhancing robustness), which is effective on real process. We can observe the performance of RHPC and confirm the practical aspect of RHPC with unmodelled dynamics through the experiment of Electric Furnace. Finally, this paper verifies the feasibility of RHPC to real process.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.1
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• pp.60-66
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• 1996

Model Based Predictive Control(MBPC) has been widely used in predictive control since 80's. GPC[1] which is the superset of many MBPC strategies a popular method, but GPC has some weakness, such as insufficient stability analysis, non-applicability to internally unstable systems. However, CRHPC[2] proposed in 1991 overcomes the above limitations. So we chose RHPC based on CRHPC for electric furnace control. An electric furnace which has nonlinear properties and large time delay is difficult to control by linear controller because it needs nearly perfect modelling and optimal gain in case of PID. As a result, those controls are very time-consuming. In this paper, we applied RHPC with equality constraint to electric furnace. The reults of experiments also include the case of RHPC with monotonic weighting improving the transient response and including unmodelled dynamics. So, This paper proved the practical aspect of RHPC for real processes.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.27.1-27
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• 2001

Reheating furnace is a facility of heating up the billet to desired high temperature in the hot charge rolling process and it consists of 3 zones. Temperature control of reheating furnace is essential for successful rolling performance and high productivity. Mostly, temperature control is carried out using PID controller However, the PID control is not effective due to the nonlinearity of the reheating furnace(i.e, presence of the interference of neighboring zones and slow response of temperature etc.). In this paper, feedback linearization method is applied to obtain a linear model of the reheating furnace. Then, controller is designed using simple predictive control method. The effectiveness of this strategy is shown through simulations.