• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.669-670
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• 2008

본 논문에서는 발전소나 민간 사업소에서 쓰이는 3.3kV급 대용량 고압모터를 진단하기 위한 휴대장비 개발에 관하여 언급하였다. 본 과제에서 개발된 휴대장비는 모터에 입력되는 3상 전압 및 전류값을 체크하여 주파수 성분등의 Power Quality 성분을 분석하는 방식으로서 모터의 진동을 검사하는 방식과 병행하여 널리 쓰이고 있으며 여러 가지 해외 제품들이 존재한다. 본 과제에서는 이러한 해외 제품을 국산화하는데 초점이 맞추어져 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.396-397
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• 2015

With the increasing utilization of high-voltage, direct current (HVDC) transmissions in modern power systems, the DC grid is becoming a hot topic in academic and practical systems. In the DC grid, one of the urgent problems is the fast clearance of the DC fault in the DC network. One preferred method is to isolate the faulty point from the DC network in a short time. The DC circuit breaker is to interrupt the overcurrent after DC faults occur. In this paper, a self-excited resonant DC circuit breaker is an easy and cheap equipment to interrupt the DC fault current. The Mayr's arc model is utilized to simulate the self-excited DC circuit breaker in a DC test system in PSCAD/EMTDC.

• 한국공작기계학회논문집
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• 제15권2호
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• pp.24-29
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• 2006

The use electron-beam(E-beam) manufacturing system provides a means to alleviate optic exposure equipment's problems. We are developing an E-beam manufacturing system with scanning electron microscope(SEM) function. The E-beam manufacturing system consist of high voltage generator, beam blanker, condenser lenses, object lenses, stigmator and stage. The development of E-beam manufacturing system is used on the method of remaking SEM's structure. The functions of SEM are developed. It is important for the test of E-beam performance. In E-beam manufacturing system and SEM, beam focus is important function. In this paper, we propose intelligent remote control function for beam focus in E-beam manufacturing system. The function extends the user's function and gives convenience.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.299-300
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• 2006

The camera and reduction mechanism that are equipment outdoors camera for general CCTV are miniaturization trend gradually. The foreign countries began to sell variableness speed type camera drivels that do DC voltage by motive power recently. But, Domestic is state that enterprise which has technology connected with this does not exist. We need optimum control program design, an internal organs technology, actuator interface and a driver design technology that have position control special quality of high accuracy as a necessary technology for CCTV camera drivers. Also, we need detailed mechanism design and a manufacture technology of camera drivers that behave variable speed essentially.

• 한국산업융합학회 논문집
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• 제7권1호
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• pp.91-96
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• 2004

Overloading of electrical equipment results in excessive currents. As the heat developed in the cables is proportional to square of the current, they get overheated. The insulation on cables is generally made of materials which are damaged easily by excessive temperature. They may therefore lose their insulating properties and lead to short circuits. Since many insulating materials are combustible, they may even catch fire if the temperature rises to their ignition temperature. In this paper, we have simulated the thermal analysis for cable according to the value of current in a overload and a short with the cable of the L's company product(600 V, VV : Four Core) using the electro-thermal finite element method(Flux2D).

• 대한전기학회논문지:시스템및제어부문D
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• 제50권11호
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• pp.550-556
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• 2001

The computerized cardiac analysis system, which acquires and analyzes the electrical activation signal propagating along the surface of the heart, is indispensible equipment for the open heart surgery and electrical cardiac study. In this paper, the design requirement and the electrical circuit analysis are performed to construct the multi-channel cardiac activation pre-amplifier necessary for a signal conditioning circuit. The general 64 channel configuration is expanded into 128 channels to enhance the spatial resolution on the mapped surface of the heart. The 128 channels pre-amplifier consists of input circuit, differential amplifier, right leg driven circuit and isolation part. It has distinct features; high voltage protection, leakage current limitation, isolation and the maximization of common mode rejection ratio with respect to the half-cell potential difference due to different electrode materials. The final pre-amplifier circuit is assembled with 8 boards, each of which composing of 16 channels.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1620-1622
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• 1998

The failure occurs in the system of the underground transmission line, the time of restoration is very long, the damage from stopping power supply is very serious and the cost of restoration is very great. because of these problems, the system and equipment must be protected from every electrical failure by installing protection unit. This study is summarized and compared the effects of configuration method of cable protection device with respect to surges in EHV (Extra High Voltage) underground transmission system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.787-790
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• 2006

This paper analyzes the principle and feature of the piezoelectric ceramic print head for the image printing of industrial inkjet plotter, and apply the Drop-on-Demand method that can adjust an ink drop size in accordance with the certain time adjustment. In order to do this study, drive frequency is selected at maximum 8.3[kHz] which can be operated within resonance frequency range of the piezoelectric ceramic. Drop controlling was realized according to pulse waveform the drive voltage, and grey-scale and satellite diminution method were applied for printing of high resolution image. A feasibility study of the result will be demonstrated by constructing the experiment equipment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.214-215
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• 1994

The VCB(Vacuum Circuit Breaker), which has been used in power distribution system, have prevented the performance of the phase modifying equipment (Condenser Bank and Shunt Reactor) and the important parts in the electric power system because of the transient voltage in opening and closing circuit. So, we developed the 25.8kV $SF_6$ gas GCB(GAS Circuit Breaker), which had the few occurance of the surge in opening & closing circuit and had the high reliability, based in our own technology.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2005년도 춘계 학술대회
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• pp.192-200
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• 2005

A high speed address recovery technique for AC plasma display panel(PDP) is proposed. By removing the GND switching operation, the recovery speed can be increased and switching loss due to GND switch also becomes to be reduced. The proposed method is able to perform load-adaptive operation by controlling the voltage level of energy recovery capacitor, which prevents increasing inefficient power consumption caused by circuit loss during recovery operation. Thus, th e technique shows the minimum address power consumption according to various displayed images, different from prior methods operating in fixed mode regardless of images. Test results with 50' HD single- scan PDP(resolution : $1366{\times}768$) show that less than 350ns of recovery time is successfully accomplished and about $54\%$ of the maximum power consumption can be reduced, tracing minimum power consumption curves.