• 대한기계학회논문집A
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• 제26권8호
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• pp.1534-1544
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• 2002

The TDCSA(Time Delay Control with Switching Action) method, which consists of Time Delay Control(TDC) and a switching action of sliding mode control(SMC), has been proposed as a promising technique in the robust control area, where the plant has unknown dynamics with parameter variations and substantial disturbances are preset. When TDCSA is applied to the plant with saturation nonlinearity, however, the so-called windup phenomena are observed to arise, causing excessive overshoot and instability. The integral element of TDCSA and the saturation element of a plant cause the windup phenomena. There are two integral effects in TDCSA. One is the integral effect occurred by time delay estimation of TDC. Other is the integral term of an integral sliding surface. In order to solve this problem, we have proposed an anti-windup scheme method for TDCSA. The stability of the overall system has been proved for a class of nonlinear system. Experiment results show that the proposed method overcomes the windup problem of the TDCSA.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.77.1-77
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• 2001

In this paper, we propose a control scheme for improving the performance of a conventional Proportional-Integral (PI) controller for Active Queue Management (AQM) supporting TCP flows. When the PI controller is used for AQM, the windup phenomenon of the integral action causes the performance degradation. Therefore we model AQM as a system with a saturator and apply anti-windup methods to the PI controller for AQM. We compare the performances of anti-windup algorithm with the conventional PI controller through ns simulations. The simulation results show that the PI controller with anti-windup method performs better than the conventional PI controller.

• 제어로봇시스템학회논문지
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• 제2권4호
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• pp.248-256
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• 1996

This paper presents an anti-reset windup (ARW) compensation method for saturating control systems with multiple controllers and/or multiloop configuration. The proposed ARW method is motivated by the concept of equilibrium point. The design parameters of the ARW scheme is derive explicitly by minimizing a reasonable performance index. In the event of saturation, the resulting dynamics of the compensated controller reflects the dynamics of the linear closed-loop system. The proposed method guarantees the total stability o fthe resulting control systems under a certain condition. An illustrative example is given to show the effectiveness of the proposed method. The paper is an extension of the results in Park and Choi[10].

• 동력기계공학회지
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• 제17권4호
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• pp.120-130
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• 2013

An adaptive PID sliding mode controller is proposed for the position control of electro-hydrostatic actuator(EHA) systems with system uncertainties and saturation in the motor. An EHA prototype is developed and system modeling and parameter identification are executed. Then, adaptive PID sliding mode controller and optimal anti-windup PID controller are designed and the performance and robustness of the two control systems are compared by experiment. It was found that the adaptive PID sliding mode control system has better performance and is more robust to system uncertainties than the optimal anti-windup PID control system.

• 제어로봇시스템학회논문지
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• 제6권10호
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• pp.894-902
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• 2000

This paper proposes a force reflection control method with a speed saturation compensation scheme for the slave manipulators having a speed saturation due to the high reduction ratio joints. When speed saturation is generated, the proposed force reflection control method not only shows an anti-windup feature in controlling the slave manipulator but also makes the master manipulator move slowly using the force reflection caused by saturation. In this way, the position of the slave manipulator tracks the reference position regardless of speed saturation. The experimental results show that the proposed control method provides excellent performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1779-1780
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• 2008

This paper presents a switching system of speed controller between PI (Proportional_Integrator) and P_LPF (Proportional_Low pass filter) to improve overshoot and slow settling time in DC motor. When the integrator is saturated in the PI controller, the error signal is integrated continuously. For preventing the state, the Anti-windup scheme is proposed. But the Anti-windup scheme dose not show stable characteristics in the whole speed command section after tuned a gain. By using P_LPF switching system these problems are improved and there is no need to tune of user hereafter, when the integrator is saturated. The proposed method is verified by the simulation results using MATLAB SIMULINK.

• 대한전기학회논문지
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• 제43권3호
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• pp.447-457
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• 1994

This paper presents a compensation method for discrete-time control systems with saturation nonlinearities to cope with the reset windup phenomena. The proposed ARW (Anti-Reset Windup) method is motivated by the concept of the equilibrium point. The design parameter of the ARW scheme is explicitly derived by minimizing a reasonable performance index. The resulting dynamics of the compensated controller exhibits the reduced model form of the unsaturated system which can be obtained by the singular perturbational model reduction method. An example is given to illustrate the effectiveness of the proposed method.

• 조명전기설비학회논문지
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• 제18권5호
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• pp.74-82
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• 2004

본 논문은 엘리베이터용 표면부착형 영구자석형 동기전동기의 속도제어를 기술하였다. 엘리베이터 전동기는 컴팩트하고 슬립형이 되어야 한다. 제안된 기법은 속도 및 토크제어를 위해 벡터제어 알고리즘을 사용하였으며, 속도제어기와 전류제어기에 windup 현상을 방지하기 위해 Anti-windup 기법을 적용하였다. 이 시스템은 컴팩트하고 저렴하게 설계하기 위하여 고속 32비트 DSP(TMS320C31-50), 고직접 논리소자 FPGA(EPF10K10TI144-3)로 수행되었다. 제안된 기법은 기계실 없는 엘리베이터용 3상 13.3[kW] 표면부착형 동기전동기로 시뮬레이션 및 실험을 통하여 결과를 확인하였다.

• 제어로봇시스템학회논문지
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• 제20권5호
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• pp.543-550
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• 2014

In many industrial processes and operations, such as power plants, petrochemical industries and ships, shell and tube heat exchangers are widely used and probably applicable for a wide range of operating temperatures. The main purpose of a heat exchanger is to transfer heat between two or more medium with temperature differences. Heat exchangers are highly nonlinear, time-varying and show time lag behavior during operation. The temperature control of such processes has been challenging for control engineers and a variety of forms of PID controllers have been proposed to guarantee better performance. In this paper, a scheme to control the outlet temperature of a shell and tube heat exchanger system that combines the PID controller with feedforward control and anti-windup techniques is presented. A genetic algorithm is used to tune the parameters of the PID controller with anti-windup and the feedforward controller by minimizing the IAE (Integral of Absolute Error). Simulation works are performed to study the performance of the proposed method when applied to the process.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권10호
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• pp.572-581
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• 2000

When the manipulator consisting of high ratio gear reducers at its joints is used as the slave manipulator in teleoperated systems, its dynamic characteristics is much slower than that of the master manipulator and it is likely to encounter the saturation in the input magnitude. The control input saturation generates an windup phenomenon that the system stability and position tracking performance of the slave manipulator are to be deteriorated. This paper proposes an force reflecting control scheme and its design method which compensates the control input saturation with absolute stability. The proposed scheme is shown to give a stable force reflection while compensating for control input saturation effectively.