• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.143-146
• /
• 1997

In this paper, we propose a fuzzy-supervised nonlinear H$_{\infty}$ controller which guarantees the robustness and has exact tracking performance for robot manipulator with system parameter uncertainty and exogenous disturbance, The proposed controller which is based on robotic H$_{\infty}$ controller has fuzzy supervisor which decides the optimal control input weighting value through fuzzy making-decision process. Owing to the fuzzy supervisor, The proposed controller can take the optimal control input. Then, we will apply the proposed controller to rigid robot manipulator to verify the performance of our controller.r.

• Proceedings of the IEEK Conference
• /
• 2003.07c
• /
• pp.2593-2596
• /
• 2003

The deadbeat properties have been well known in designing digital control systems. But recently several researchers proposed a CDBC(Continuout-time DeadBeat Controller) in continuous time. They used delay or smoothing elements from the finite Laplace Transform. A delay element is made by the exponential terms. A smoothing element is used to smooth the digital control input. And eventually the process is argumentd with smoothing elements and then well-known digital deadbeat controller is designed Sometimes samplings are done in continuous time systems and some hold devices are used to relate to digital systems. So multirate sampling may enhance the efficiency of the CDBC. A DC servo motor is chosen for implementing CDBC algorithm. Especially Outputs according to the variable input and disturbance are simulated. by use of Matlab Simulink.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.4 no.2
• /
• pp.175-183
• /
• 1999

For fast response of the dc output voltage in P\hi1'v1 converter, it is desirable that the relation of power balance of the i input and output terminals is introduced to the system modeling. In this case, controller desi밍1 is not easy since the m model is nonlinear. In this paper, a nonlinear control them${\gamma}$ using input-output feedback linearization is used to solve t the nonlinear problem of the system. By nonlinear control. the voltage transient response can be faster, and it is also p possible to control the output voltage to be constant with smaller output filter capacitance for load disturbance.

• Proceedings of the KIPE Conference
• /
• 1997.07a
• /
• pp.89-96
• /
• 1997

A robust speed control scheme for a brushless DC(BLDC) motor using an adaptive input-output linearization technique is presented. By using this technique, the nonlinear motor model can be linearized in Brunovski canonical form, and the desired speed dynamics can be obtained based on the linearized model. This control technique, however, gives an undesirable output performance under the mismatch of the system parameters and load conditions. For the robust output response, the controller parameters will be estimated by a model reference adaptive technique where the disturbance torque and flux linkage are estimated. The adaptation laws are derived by the Popov's hyperstability theory and positivity concept. The proposed control scheme is implemented on a BLDC motor using the software of DSP TMS320C30 and the effectiveness is verified through the comparative experiments.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.9 no.5
• /
• pp.65-72
• /
• 2000

This paper presents the study of the tension control in a web transfer system. In this study the sliding mode controller is applied to a time-varying nonlinear mathematical model. The model was derived to consider the effects of changing the roll radius in tension variation during winding and unwinding. The uncertainty in modeling may be due to unmodelled dynamics, on variations in system model. Designed sliding mode controller made the system error always staying in the suggested surface from the beginning. Through this, system is maintained to be robust against a disturbance and uncertainty. To verify the designed controller has a good performance, various inputs such as desired velocity, step input, and trapezoidal input are applied. When the sliding mode controller was used, the system(the tension control) performance was improved comparing to the PID controller. The robustness of the controller with respect to an estimation error was verified through simulations.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.8
• /
• pp.689-696
• /
• 2000

In this paper we propose an eminent controller for wheeled mobile robots. This controller consists of an input-output linearization controller trying to stabilize the system and a neural network controller to compensate for uncertainties. The uncertainties are divided into two parts. First unstructured uncertainties include the elements related with system order such as friction disturbance. Second structure uncertainties are the incorrect system parameters A neural network structure of the proposed overall controller learns structural errors of the wheeled mobile robots with uncertainties and includes the neural network output. This controller learns quickly the model and has good tracking performance Simulation results show that the proposed controller is more efficient than analog controllers.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.60 no.4
• /
• pp.181-185
• /
• 2011

Due to the increasing of nonlinear loads such as converters and inverters connected to the electric power distribution system, and extensive application of harmonic generation sources with power electronic devices, disturbance of the electric power system and its influences on industries have been continuously increasing. Thus, it is difficult to construct accurate load model for active and reactive power in environments with harmonics. In this research, we develop current harmonics estimation method based on Extreme Learning Machine (ELM) with fast learning procedure for residential loads. Using data sets acquired from various residential loads, the proposed method has been intensively tested. As the experimental results, we confirm that the proposed method makes it possible to effective estimate current harmonics for various input voltage.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.7
• /
• pp.8-16
• /
• 2013

This paper investigates the electrical characteristics of popular power converters such as a half-bridge rectifier, a full-bridge rectifier, a buck converter, and an inverter when the arc is occurred at the input and the output of each converter. In order to generate an artificial arc, the arc generator has been implemented according to the design guideline suggested in UL1699. After that, the trend of the input and output voltage variation and the switching stress of the devices are analyzed. From the analysis, it has been confirmed that the generated arc causes an uncertain operation to the power converters. To reduce the unexpected disturbance effect of the arc, the capacitor adjustment method has been proposed, and its superiority has been experimentally verified.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.1206-1212
• /
• 1993

In this paper, an variable structure system with an integral-augmented sliding surface is designed for the improved robust control of a uncertain multi-input multi-output(MIMO) system subject to the persistent disturbances. To effectively remove the reaching phase problems, the integral augmented sliding surface is defined, then for its design, the eigenstructure assignment technique is introduced. To guarantee the designed performance againts the persistent disturbance, the stabilizing control for multi-input system is also designed. The stability of the global system and performance robustness are investigated. The example will be given for showing the usefulness of algorithm.

• 제어로봇시스템학회:학술대회논문집
• /
• 1994.10a
• /
• pp.558-560
• /
• 1994

In this paper, a memoryless H$_{\infty}$ controller for linear systems with state and input delays is presented. The proposed controller is a delay independent stabilizer which reduces the H$_{\infty}$ norm of the closed loop transfer function, from the disturbance to the controlled output, to a precribed level. The controller is obtained by solving a minimization problem involving linear matrix inequalities.s.