• 한국지능시스템학회논문지
• /
• 제18권6호
• /
• pp.762-767
• /
• 2008

본 논문에서는 TS 퍼지 모델로 표현되는 시간 지연 비선형 시스템에 대한 $L_{\infty}$ 이득 상태 제한 퍼지 제어기를 제안한다. 이 위해 먼저 TS 퍼지 모델을 이용하여 시간 지연 비선형 시스템을 모델링한다. 다음 이 퍼지 모델을 기본으로 $L_{\infty}$ 이득을 얻기위해 퍼지 상태 궤환 제어기를 설계한다. 마지막으로 $L_{\infty}$ 이득을 얻기 위한 충분조건을 유도한다. 충분조건은 선형 행렬 부등식의 형태로 공식화 한다. 마지막으로 몇 가지 예제를 통하여 제안된 제어기의 효율성을 증명한다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 B
• /
• pp.1137-1139
• /
• 1996

Feedback Linearization technique needs the exact cancellation of nonlinearity which restricts its application to real environment. To overcome these shortcomings, High-pin feedback is good remedy to this problem. In this paper, we briefly survey the high-gain feedback control technique and show some conditions for applying this method to nonlinear systems. In order to use this technique in real situation, some properties of ${\varepsilon}$-bound and semi-global stabilization are discussed.

• Transactions on Control, Automation and Systems Engineering
• /
• 제2권2호
• /
• pp.104-109
• /
• 2000

In this paper, the output feedback stabilizing problem is solved using any given state feedback control law. Compared to the linear systems is not so straightforward for nonlinear systems. We briefly explain the intrinsic obstructions for this problem and provide new output feedback scheme which achieves the semi-global stabilization with the high-gain state observer. THe overall uniform observability of the plant. Therefore, the result can be regarded as an extension of the separation principle for linear systems in some aspect.

• 전기전자학회논문지
• /
• 제6권2호
• /
• pp.128-135
• /
• 2002

선형 플랜트의 극한 이득과 주기를 찾기 위해 포화함수를 이용하여 자기 진동을 발생 시켰다. 포화함수 사용으로 극한이득과 주기의 정확성을 높였다. 발견한 극한 이득과 극한 주기는 PID 제어기 값을 구하는데 사용하였다. 정적인 부하 왜란 등이 있는 경우 비대칭 진동이 발생할 수 있다. 발생하는 비대칭 자기 진동을 분석하였고 분석결과로부터 극한 이득과 주기를 찾는 방법을 제안하였다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
• /
• pp.321-326
• /
• 1993

A gain scheduling approach for the suspension control of a nonlinear MAGLEV System is presented. We show that this technique is ver useful for improving not only performance to the operational disturbances originating aerodynamic force but also robustness to the uncertainty of payload. As a scheduling variable, even though the external disturbance need to be estimated in real time, but the additive measurement is not required to do it. Some simulations show that the gain scheduling control system performs very well comparing with other method using a nonlinear feedback linearization or a fixed gain linear feedback.

• 전자공학회논문지S
• /
• 제34S권9호
• /
• pp.60-66
• /
• 1997

WE consider the stabilization of a class of multivariable nonlinear system using variable structure output feedback control. A high-gain observer is used to estimate state variable while rejecting the effect of the disturbances. We design a globally bounded output feedback variable structure controller that semi-globally stabilize the closed-loop system, while state variables do not exhibit a peaking.

• Journal of Electrical Engineering and information Science
• /
• 제3권2호
• /
• pp.184-192
• /
• 1998

In this paper, we present a nonlinear feedback linearization-full order observer/sliding mode controller (NFL-FOO/SMC), to obtain smmoth control as a linearized controller in a linear system (or to cancel the nonlinearity in a nonlinear system), and to solve the problem of the unmeasurable state variables as in the conventional SMC. The proposed controller is obtained by combining the nonlinear feedback linearization-sliding mode control (NFL-SMC) with the full order observer (FOO)and eliminates the need to measure all the state variables in the traditional SMC. The proposed controller is applied to the nonlinear power system stabilizer (PSS) for damping oscillations in a power system. The effectiveness of the proposed controller is verified by the nonlinear time-domain simulations in case of a 3-cycle line-to-ground fault and in case of the parameter variation for the AVR gain K\ulcorner and for the inertia moment M.

• 대한전기학회논문지
• /
• 제45권2호
• /
• pp.273-282
• /
• 1996

This work is conceded with the estimation of output derivatives and their use for the design of robust controller for linear systems with system uncertainties due to modeling errors and disturbances. It is assumed that a nominal transfer function model and quantitative bounds for system uncertainties and known. The developed control schemes are shown to achieve regulation of the system output and ensures boundedness of the system states without imposing any structural conditions on system uncertainties and disturbances. Output derivative estimation is first conducted through restructuring of the plant in a specific parameterization. They are utilized for constructing robust nonlinear high-gain feedback controller of a SMC(Sliding Mode Control)type. The performances of the developed controller are evaluated and shown to be effective and useful through simulation study.

• Journal of Electrical Engineering and information Science
• /
• 제3권2호
• /
• pp.193-201
• /
• 1998

In this paper, the standard Dole, Glover, Khargoneker, and Francis (abbr. : DGKF 1989) H\ulcorner controller (H\ulcornerC) is extended to the nonlinear feedback linearization-H\ulcorner/sliding mode controller (NFL-H\ulcorner/SMC), to tackle the problem of the unmeasurable state variables as in the conventional SMC, to obtain smooth control as the linearized controller in a linear system, and to improve the time-domain performance under a worst scenario. The proposed controller is obtained by combining the H\ulcorner estimator with the nonlinear feedback linearization-sliding mode controller (NFL-SMC) and it does not need to measure all the state variables as in the traditional SMC. The proposed controller is applied as a nonlinear power system stabilizer (PSS) for the improvement of the power system damping characteristics of an single machine infinite bus system (SMIBS) connected through a double circuit line. The effectiveness of the proposed controller is verified by nonlinear time-domain simulation in case of a 3-cycle line-to-ground fault and in case of the parameter variations for the AVR gain K\ulcorner and for the inertia moment M.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.395-398
• /
• 1996

In this study, when the nonlinear overhead crane which allows simultaneously travel and traverse motion moves a desired transport route, the object suspended the end of rope does undesirable swing motion. Nonlinear overhead crane pertubes in the vicinity of an operating point, therefore the nonlinear overhead crane is modified to linear overhead crane for the operating point. The linear overhead crane was controlled to swing angles of the object by the ratio of torque inputs to motors of the girder and the trolley. As a basis for the result of the linear overhead crane, the nonlinear overhead crane was controlled swing angles of the object and positions of the overhead crane without collision with environmental equipment by partial state feedback control.