• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.73-77
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• 2002

The requirements for higher productivity call for high speed of the machine tool axes. Iron core type linear DC motor is growly accepted far a viable candidate of the high speed machine tool feed unit. LDM, however, has inherent disturbance force components: cogging and force ripple. These disturbance force directly affects tracking accuracy of the carrage and must be eliminated or reduced. Reducing motor ripple, this paper adapted the feed forward compensation method and neural network control. Experiments carried 7ut on the linear motor test setup show that this control methods is usable in order to reduce the motor ripple.

• Journal of Power System Engineering
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• v.4 no.3
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• pp.62-71
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• 2000

A mathematical modeling for a magnetic levitation system is proposed using the Taylor series expansion of differential function for obtaining linearity. It is confirmed that this kind of linear approximation method can be used to the modeling of a magnetic levitation system. The two-degree-of-freedom optimal servo system for a constant reference signal is proposed using the LQ optimization technique. An additional state feedback is introduced at the output of the integrator to cancel the integral action for reference signal if there is no modeling error of the plant and no disturbance input to the plant. When the modeling error or the disturbance input exists, the integral effect appears. The system has a free parameter which can b used to tune the effect of the integral compensation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.555-558
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• 1995

In designing the anti-sway controller for crane system in the industrial field, one of the basic problem is to keep the stability of system, even if the mathematical model of the plant is not exact and disturbance exists. Form this point of view, a two-degree-of-freedom(2DOF) servo controller effact to the system in which the integral compensation is effctive only when a modeling error and/or a disturbance input exist. In this paper, the change of load weight and variation of wire rope length considered as the structured uncertainty, and design the 2DOF servo contorller using independently the informations of reference signal and control output with both feedforward and feedback. The effectivenss is proved through the results for the anti-sway system in the system with the position control of trolley.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.6
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• pp.78-82
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• 1995

It is needed to robust control for D.C. servo motor according to industrial automation. However, when a motor has an effect of disturbance and variable load, it is very difficult to guarantee the robustness of the system. as a compensation way of solving this problem, in this paper, a expert supervisory control method for motor control system is presented. Expert supervisory controller is designed by error and error change, and nth control input is decided by the addition of (n-1)th control input and inference amount of increase or decrease. Control input of expert supervisory control is transmitted to input, and the disturbance effect decrease remarkable by control input. The robustness of D.C. servo motor using expert supervisory control is demonstrated by the computer simulation.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.450-455
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• 1989

In this paper we investigate the application to the motion control of n-link robotic manipulators of recently developed stable factorization approach to tracking and disturbance rejection. Given control scheme consists of an approximate "Computed Torque" based upon a simplified model together with additional state feedback and feedforward compensation, and then, nonlinear control gain has more useful than constant control gain to guarantee robustness to parameter uncertainty and external disturbance. At this stage, we design high gain nonlinear state feedback controller and simulate this controller at the SCARA type robot manipulator of two joint.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.261-263
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• 1995

The continuous sliding mode controller with disturbance observer for the tracking control of permanent magnet synchronous motor(PMSM) is presented. In spite of the robust performance of variable structure control, there exists an undesirable chattering problem, which may be very harmful in some cases. To alleviate the problem, continuous sliding mode controller with continuous saturation function is proposed and also the prescribed performance can be obtained by efficient compensation of disturbance. Experimental results using 7.5 kW, 4000 rpm motor which is controlled by TMS320C30 DSP, are shown to demonstrate the usefulness of the proposed algorithm.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.351-354
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• 1987

In this paper, an adaptive control scheme is applied to the speed control system of a synchronous AC servo motor. The adaptive control system using Ioannou's modified adaptation law is shown to be robustly stable in the presence of current control error and load torque disturbance. The computer simulation demonstrates the rapid compensation of rotor speed deviation due to load torque disturbance.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2799-2801
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• 2000

Robust control for DC motor is needed according to the highest precision of industrial automation. However, when a motor control system with PID controller has an effect of load disturbance, it is very difficult to guarantee the robustness of control system. In this paper, PID-Expert hybrid control method for motor control system as a compensation method solving this problem is presented. If PID control system is stable, the Expert controller is idle. if the error hits the boundary of the constraint. the Expert controller begins operation to force the error back to the constraint set. The disturbance effect decrease remarkably, robust speed control of DC motor using PID-Expert Hybrid controller is demonstrated by the simulation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.8
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• pp.363-367
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• 2003

Robust control for feedback control system is needed according to the highest precision of industrial automation. However, when a feedback control system has an effect of disturbance, it is very difficult to guarantee the robustness of control system. As a compensation method solving this problem, in this paper, Hybrid control method of feedback and Differential Supervisory controller is presented. A Feedback Controller is operated as a main controller, A Differential Supervisory Controller is a controller which operates only when some undesirable phenomena occur, e. g., when the error hits the boundary of constraint set. The robust control function of Differential Supervisory Controller, as a assistant controller is operated when state is unstable by disturbance. it demonstrated by speed control of motor.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.1
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• pp.111-116
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• 1998

Robust control for DC servo motor is needed according to the highest precision of industrial automation. However, when a motor control system with PID controller has an effect of load disturbance, it is very difficult to guarantee the robustness of control system. As a compensation method solving this problem, in this paper, PID-neural network hybrid control method for motor control system is presented. The output of neural network controller is determined by error and rate of error change occurring in load disturbance. The robust control of DC servo motor using neural network controller is demonstrated by computer simula tion.a tion.