• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제31권6호
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• pp.433-436
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• 2018

A total internal reflection (TIR) linear lens of size $190(W){\times}5(D){\times}2.1(H)mm^3$ has a directivity of $25^{\circ}$ and was made of a polydimethysiloxane (PDMS) silicone resin with a refractive index of 1.4 and a transmittance of 93% at 365 nm UV wavelength. A light source with a size of $190{\times}25.5mm^2$ was fabricated by installing a TIR linear lens on a chip on board (COB) type LED module mounted with a $1.1{\times}1.1mm^2$ size UV LED. The optical characteristics of the light source showed a maximum irradiation density of $3,840mW/cm^2$ at a working distance of 5 mm and a high uniformity of 91.6% over a $150{\times}25mm^2$ irradiation area. The thermal characteristics of the light source were measured at a supply current of 500 mA. The saturation temperature was reached after 30 min of operation, and measured to be $95^{\circ}C$.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 한국조명전기설비학회 2007년도 추계학술대회 논문집
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• pp.323-326
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• 2007

In this paper, the basic experiment, electrolytic cell design and basic manufacturing have been made to interpret the characteristics of Hydrogen-Oxygen-Gas-Generator. As for the detailed matters, the data research on basic technology on Hydrogen-Oxygen-Gas and analysis on characteristics of Hydrogen-Oxygen-Gas from basic experiment. Also the experiment of characteristics and comparative evaluation between constant current source using SCR converter from existing method and constant current source using new phase shift PWM control method converter. As results when it has injected constant DC current, we has compared Gas quantities by variable ripple frequencies using phase shift PWM control method converter. Therefore, in linear region, it has not different Gas quantities by constant DC current and by phase shift PWM control method converter. Also, it has increased Gas quantities wilder linear region when put ripple frequency at saturation region. Through, Gas quantities and input rower, it has acquired higher input power per Gas quantities at put pulse current. Therefore, when designing converter or inverter for electrolysis, which has ripple current.

• Journal of Advanced Marine Engineering and Technology
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• 제31권2호
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• pp.190-196
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• 2007

This paper presents the 3D finite element analysis of the Contact-less Power Supply(CPS) with linear servo motor. The primary, secondary self and leakage inductances of the contact-less power supply and the capacitances of a resonant circuit are calculated by the finite element analysis using current source. The voltage source is used to do accurate analysis of the characteristics of the contact-less power supply. The CPS with the linear servo motor is proposed. The characteristics analysis of the contact-less power supply considering the linear servo motor is done.

• Proceedings of the IEEK Conference
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.208-211
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• 1999

Abstract - Electrical characteristics or asymmetric n-MOSFET's with different source and drain geometry are experimently investigated using test structures having various gate width. Saturation drain current and resistance in linear region are estimated by a simple schematic model, which consists of conventional device having parasitic resistor. A comparison of experimental results of symmetric and asymmetric devices gives the parasitic resistance caused by abnormal device structure. The suggested model shows good agreement with the measured drain current for both forward- and reverse-modes.

• Proceedings of the KIEE Conference
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• 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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• pp.88-92
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• 2007

In this paper, the basic experiment, electrolytic cell design and basic manufacturing have been made to interpret the characteristics of Hydrogen-Oxygen-Gas-Generator. As for the detailed matters, the data research on basic technology on Hydrogen-Oxygen-Gas and analysis on characteristics of Hydrogen-Oxygen-Gas from basic experiment. Also the experiment of characteristics and comparative evaluation between constant current source using IGBT converter from existing method and constant current source using new phase shift PWM control method converter. As results when it has injected constant DC current, we has compared Gas quantities by variable ripple frequencies using phase shift PWM control method converter. Therefore, in linear region, it has not different Gas quantities by constant DC current and by phase shift PWM control method converter. Also, it has increased Gas quantities wilder linear region when put ripple frequency at saturation region. Through, Gas quantities and input power, it has acquired higher input power per Gas quantities at put pulse curren. Therefore, when designing converter or inverter for electrolysis, which has ripple current.

• Journal of Power Electronics
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• 제11권6호
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• pp.931-937
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• 2011

This paper presents a method for the performance improvement of a shunt active power filter (SAPF) using the indirect current control (ICC) scheme. Compared to the conventional direct current control (DCC) scheme, the ICC gives better performance with a lower number of sensors. A simplified and efficient control algorithm using a low cost Intel 80C196KC microcontroller is implemented using only two current sensors for the source current and one voltage sensor for the DC-link voltage of the SAPF circuit. The objective is to eliminate harmonics and to compensate the reactive power produced by non-linear loads such as an uncontrolled rectifier feeding an inductive load. The APF is realized using a three phase voltage source inverter (VSI) with a dc bus capacitor. Experimental results are presented to prove the better performance of the ICC method over the DCC one.

• Journal of Institute of Control, Robotics and Systems
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• 제14권4호
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• pp.385-391
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• 2008

To effectively cope with a complexity of kinematic metrology due to workspace enlargement of the planar stage, the linear induction motor is suggested as its new driving source. Especially, the linear induction motor under uniform plate type of secondary doesn't inherently have a periodical force ripple which is generally shown in the brushless DC motor. But, it presents a poor transient characteristic at zero or low speed zone owing to time delay of flux settling, resulting in slow response. To improve the servo property of linear induction motor and apply successfully it to the precision stage, this paper discusses a modified vector control methodology. The controller has a novel input form, fixed d-axis current, q-axis current and forward-fed DC current, to control thrust force and normal force of the linear induction motor independently. Influence of the newly introduced input and the feasibility of controller are validated experimentally.

• Journal of Power Electronics
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• 제9권3호
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• pp.403-409
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• 2009

Automatically tuned passive filters can improve power quality to a great extent in power systems. A novel three-phase shunt auto-tuned filter is designed to effectively compensate source current harmonics and to provide reactive power required by the non-linear load, which draws a highly reactive, harmonic-rich current from the supply. An artificial neural network (ANN) based controller selects filter component values in accordance with reactive power requirement and harmonic compensation. Traditional passive filters are permanently connected to the system and draw large amounts of source current even under light load conditions. By using auto-tuned filters, the passive filter components can be controlled according to load variations and, hence, draw only required source currents. The selection is done by the ANN with the help of a properly tuned knowledge base to provide instantaneous compensation using a digital controller.

• The Transactions of the Korean Institute of Electrical Engineers A
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• 제48권11호
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• pp.1388-1393
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• 1999

A more reliable algorithm for detecting a high impedance fault (HIF) requires fault currents at the relaying point containing information of load condition as well as HIF characteristics. This paper presents a modeling method of an HIF in a distribution system using EMTP. From the voltage and current waveforms of HIF experiment, the voltage-current characteristic is obtained and then piecewise linearized. The proposed method gets several points on the linearized voltage-current curve and then represents nonlinearity as piecewise linear resistances using Transient Analysis of Control Systems (TACS) in EMTP. Thus, an HIF is represented as a voltage source in the first and third quadrants of voltage-current plane. The method is implemented in EMTP and thus the voltage and current at the relaying point can be obtained when an HIF occurs. In this paper, an HIF was simulated on various load conditions and fault conditions in 22.9 [kV] distribution systems.

• Journal of Power Electronics
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• 제17권3호
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• pp.610-620
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• 2017

The Finite Control Set-Model Predictive Controller (FCS-MPC) for quasi Z-Source Inverters (qZSIs) is designed to reduce the number of sensors by proposing a current observer for the inductor current. Unlike the traditional FCS-MPC algorithm, the proposed model removes the inductor current sensor and observes the inductor current value based on the deposited prior optimized state as well as the capacitor voltage during this state. The proposed observer has been validated versus a typical MPC. Then, a comparative study between the proposed Modified Finite Control Set-Model Predictive Controller (MFCS-MPC) and a linear PID controller is provided under the same operating conditions. This study demonstrates that the dynamic response of the control objectives by MFCS-MPC is faster than that of the PID. On the other hand, the PID controller has a lower Total Harmonic Distortion (THD) when compared to the MFCS-MPC at the same average switching. Experimental results validate both methods using a DSP F28335.