• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.39-40
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• 2008

본 논문은 네트워크 기반 제어시스템(NCS: Networked Control Systems)모델매칭 제어기법을 적용한 효율적인 제어알고리즘을 제안한다. 비선형의 특징을 가지는 제어기 및 관측기의 시간지연을 Pade 근사법으로 선형화하여 선형시스템 이론을 적용한 모델매칭 제어기를 설계하였다. 또한, 제어기의 차수를 줄이기 위하여 저차시스템으로 근사화하여 그 타당성을 검증하였다. 제안한 제어알고리즘의 타당성 및 신뢰성을 검증하기 위하여 컴퓨터 시뮬레이션을 실시하였으며 기존의 PID 제어기법과 비교분석하였다.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.124-129
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• 2021

In this paper, an optimal controller design that guarantees absolute stability is proposed. The order of application of the thesis determines whether the delay time is included, and if the delay time is included, the delay time is approximated through the Pade approximation method. Then, the open loop transfer function for the process model and the controller transfer function is obtained, and the absolute stability interval is calculated by the Routh-Hurwitz discrimination method. In the last step, the optimal Proportional and Integral and Derivative(PID) control parameter value is calculated using a genetic algorithm using the interval obtained in the previous step. As a result, it was confirmed that the proposed method guarantees stability and is superior to the existing method in performance index by designing an optimal controller. If we study the compensation method for the delay time in the future, it is judged that better performance indicators will be obtained.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.18 no.4
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• pp.16-20
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• 2010

The dynamic characteristics of flight sensors is obtained by a simple method that deploys a pendulum with a rotary encoder. The encoder output is used with kinematic relations to derive reference signals for various flight sensors, including position, velocity, attitude, and angular rate sensors as well as accelerometer and magnetic sensors. A time delay of 0.4 seconds is found in the position output of the flight sensor under investigation. A logic to compensate for the time delay using a velocity information is proposed and validated in flight tests.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.6
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• pp.1-8
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• 2005

The calculation of parameters of a process model is modified to find better sliding mode controller for a process. A design method by Camacho has such problems as chattering and overshoot due to the Taylor the approximation errors for the time delay term of the first order model. In this paper, a new design technique for a sliding mode controller is proposed by introducing the modified Pade approximation considering the weight factor. With the proposed method, the process response can be directly used to estimate the system parameters without any numerical processing.

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.2
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• pp.71-75
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• 2002

We propose a new method to deal with the optimized auto-tuning for the PID controller which is used to the process-control in various fields. First of all, in this method, 1st order delay system with dead time which is modelled from the unit step response of the system is Pade-approximated, then initial values are determined by the Ziegler-Nichols method and deciding binary strings of parents generation using by the fitness values of genetic algorithms, we perform selection, crossover and mutation to generate the descendant generation. The advantage of this method is better than the Ziegler-Nickels method in characteristic of output, and has extent of applying without limit of K, L, T parameters.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.299-304
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• 1996

This paper studies the rational approximation of multiple input delay systems using the Hankel singular values and vectors, which are the soultion of a transcendental equation. Rational approximatants are obtained from output normal realizations which are constructed by the Hankel singular values and vectors. Consequently, it is shown that rational approximants by output normal realization preserve intrinsic properties of time delay systems than Pade approximants.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.3
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• pp.60-65
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• 2000

We propose a new method to deal with the optimal gain self-tuning of the PID controller which is used to industrial process control in various fields. First of all, in this method, first order delay system which was modeled from the unit step response of the system is Pade-approximated, then initial values are determined by the Ziegler-Nickels method. Finally, we can find the parameters of Pm controller so as to maximize the fuzzy inferencl function which includes the maximum overshoot, damping ratio, rising time and settling time. The proposed method also shows good adaptability for variations in characteristics and dead time of the system.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.3
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• pp.1-12
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• 2001

We consider the robust control problem for non-minimum phase(NMP) systems with parametric uncertainty. First, a new method that translates such an uncertain NMP system into a interval family of minimum phase(MP) transfer functions followed a time delay term in the form of Pade' approximation is presented. The controller to be proposed consists of a compensator with Smith predictor structure, so that it can compensate the time delay behaviour due to NMP plant. Therein, the main feedback controller for a family of MP plants has been designed by using quantitative feedback theory(QFT) such that satisfies the robust stability against the structured uncertainty. The stability and performance of overall system are examined through an illustrative example.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.63-70
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• 1999

This paper is proposed a new method to deal with the optimized auto-tuning for the Pill controller which is used to the process-control in various fields. First of all, in this method, 1st order delay system with dead time which is modelled from the unit step response of the system is Pade-approximated, then initial values are determined by the Ziegler-Nichols method. So we can find the parameters of Pill controller so as to minimize the fuzzy criterion function which includes the maximum overshoot, damping ratio, rising time and settling time. Finally, after studying the parameters of Pill controller by Backpropagation of Neural-Network, when we give new K, L, T values to Neural-Network, the optimized parameter of Pill controller is found by Neural-Network Program.rogram.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.8 no.3
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• pp.64-70
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• 1994

We propose a new method to deal with optimal auto-tuning of the PID controller which is used to process control in various fields. First of all, in this method, 1st order system which was modeled from the unit step response of the system is Pade-approximated, then initial values are determined by the Ziegler-Nichols method. Finally, we can find the parameters of PID controller so as to maximize the fuzzy criterion function which includes the maximum overshoot, damping ratio, rising time and settling time. The Proposed method also shows good adaptability for variations in characteristics and dead m e of the system.