• 대한전기학회논문지:시스템및제어부문D
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• 제54권4호
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• pp.228-234
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• 2005

In this paper, we proposed a self tuning adaptive fuzzy sliding control algorithms using gadient descent method to reduce chattering phenomenon which is viewed in variable control system. In design of FLC, fuzzy control rules are obtained from expert's experience and intuition and it is very difficult to obtain them. We proposed an adaptive algorithm which is automatically updated by consequence part parameter of control rules in order to reduce chattering phenomenon and simultaneously to satisfy the sliding mode condition. The proposed algorithm has the characteristics which are viewed in conventional VSC, e.g. insensitivity to a class of disturbance, parameter variations and uncertainties in the sliding mode. To demonstrate its performance, the proposed control algorithm is applied to an inverted pendulum system. The results show that both alleviation of chattering and performance are achieved.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1125-1128
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• 1999

This paper presents a speed controller for the Sinusoidal type BLDC motor using the sliding mode. Since the sliding mode control has some practical limitations such as the chattering phenomenon and reaching phase problems, the technique of overcoming these limitations is proposed in a practical realization. This proposed speed control technique is composed of an smooth integral variable structure control(IVSC), and chattering prediction method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1850-1851
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• 2006

The sliding mode control is acceptable for Autonomous Underwater Vehicle(AUV), since the dynamics of AUV are highly nonlinear and have several parameter uncertainty such as the added mass terms, the hydrodynamic coefficients. The sliding mode control can deal well with nonlinearity of the system and offers a robustness to controller with parameter uncertainty. Since sliding mode control has the defect of chattering problem, only in ideal case the actuator can respond by control law. Therefore we propose the sliding mode control with non-chattering. And computer simulations illustrate the performance of the proposed controller.

• Smart Structures and Systems
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• 제19권5호
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• pp.577-585
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• 2017

In this paper, an adaptive fuzzy sliding mode controller (AFSMC) is designed to reduce dynamic responses of seismically excited structures. In the conventional sliding mode control (SMC), direct implementation of switching-type control law leads to chattering phenomenon which may excite unmodeled high frequency dynamics and may cause vibration in control force. Attenuation of chattering and its harmful effects are done by using fuzzy controller to approximate discontinuous part of the sliding mode control law. In order to prevent time-consuming obtaining of membership functions and reduce complexity of the fuzzy rule bases, adaptive law based on Lyapunov function is designed. To demonstrate the performance of AFSMC method and to compare with that of SMC and fuzzy control, a linear three-story scaled building is investigated for numerical simulation based on the proposed method. The results indicate satisfactory performance of the proposed method superior to those of SMC and fuzzy control.

• International Journal of Control, Automation, and Systems
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• 제2권3호
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• pp.354-361
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• 2004

To improve fault isolation performance of the Bayes isolator, this paper proposes the Fuzzy-Bayes isolator, which uses the Fuzzy-Bayes classifier as a fault isolator. The Fuzzy-Bayes classifier is composed of the Bayes classifier and weighting factor, which is determined by fuzzy inference logic. The Mahalanobis distance derivative is mapped to the weighting factor by fuzzy inference logic. The Fuzzy-Bayes fault isolator is designed for the BLDC motor fault diagnosis system. Fault isolation performance is evaluated by the experiments. The research results indicate that the Fuzzy-Bayes fault isolator improves fault isolation performance and that it can reduce the transition region chattering that is occurred when the fault is injected. In the experiment, chattering is reduced by about half that of the Bayes classifier's.

• 대한전자공학회논문지
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• 제26권4호
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• pp.27-34
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• 1989

可變 構造 시스템 理論을 適用한 適應 모델 追從 制御器를 設計 하였다. 變形된 슬라이딩 모드 條件을 滿足시키는 提案된 制御器는 狀態 軌跡의 슬라이딩 平面 到達 速度를 改善하고 슬라이딩 모드에서 채터링의 크기를 줄이도록 한다. 슬라이딩 平面 近處의 領域에서 制御入力을 바꿈으로써 채터링을 줄이고 이 結果를 컴퓨터 시뮬레이션을 통하여 立證하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.360-364
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• 2001

In this paper, a novel method of reaching law variable structure control based on fuzzy rules is present, which is that the reaching law parameters is on-line adjusted by fuzzy rules. This method is used in a digital ac position servo system, the experiment results show that the system designed by this method has both satisfactory quality and very smaller chattering.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.286-291
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• 1991

This paper discusses sliding made control of robot manipurators assuming that nonlinear terms, which are inertia term, Coriolis force term and centrifugal taffn, are external disturbances. We obtained the unknown parameter of its linear terms by Signal Compression Method. We propose a new control input algorithm to decrease chattering in the application of sliding mode control of manipulator whose nonlinear components are regarded as disturbances. In this experiments, we used DSP(Digital Signal Processor) controller to suppress chattering by obtaining a quick switching speed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.297-299
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• 1995

In this paper, a disturbance observer with binary control is proposed to suppress the chattering of sliding mode observer in estimation of the external disturbance. Binary control has the properly of chattering alleviation in addition to advantages of the conventional sliding mode control. As a simulation result, it is confirmed that the robust and high precision position control is possible by the proposed binary observer.

• 항공우주기술
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• 제12권2호
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• pp.108-117
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• 2013

가스발생기용 산화제 개폐밸브는 파일롯 공압으로 포핏을 열고 스프링 힘에 의해 닫음으로써 로켓엔진의 추진제 유량을 제어한다. 현재 개발 중인 산화제 개폐밸브는 액추에이터에서 압력을 제거하면 닫히도록 설계되어 있다. 그러므로 밸브의 성능을 평가하기 위해 밸브가 열리고 닫히는 특성에 따라 힘 평형 상태를 분석할 필요가 있다. 밸브가 닫히기 시작하는 시점의 작동 유체의 압력을 결정하고, 포핏이 열리는 시점의 압력을 결정되어 힘평형이 설계되어 있다. 인증시험 수준에서의 극저온 유동 시험 하에서 채터링 현상은 금속 기밀부에서 다량의 누설이 발생했다. 힘평형 계산을 이용한 산화제 밸브의 채터링이 발생된 시점의 압력은 약 11 bar로 예측 된다.