• 조명전기설비학회논문지
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• 제22권2호
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• pp.71-79
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• 2008

철도 고압배전선로의 경우 궤도를 따라 양방향으로 선로연변에 통신 및 신호설비와 병행하여 가공 또는 지중선로로 설치되어 있다. 가공선로의 경우에는 대기중에 노출되어 있어 뇌격, 폭풍우, 염해 등 자연현상으로 인한 고장발생이 다수 발생하고 있으며, 이에 따른 보호장치의 오 부동작이 빈번하게 발생하고 있다. 철도 고압배전선로에서 발생하는 사고 중 가장 많은 것은 1선 지락이지만 이밖에 선간 단락, 심할 경우에는 3선 지락(단락)으로까지 진전되는 사고가 있을 뿐만 아니라 단선 사고까지 발생하는 경우도 있다. 따라서 사고를 방지하기 위해서는 보다 상세한 점검보수가 필요하며, 고장발생시 조기발견과 신속한 고장처리는 철도안전수송에 중요하다. 본 논문에서는 철도 고압배전계통의 주류를 이루게 될 22.9[kV] 직접접지 계통을 대상으로 고장 발생시 고장 위치를 신속하게 표정할 수 있는 고장점 표정 알고리즘 개발을 위해 22.9[kV] 고압배전계통을 모델링 하여 특성해석과 고장해석을 수행하였고, 정확한 고장점 표정이 가능한 반복계산법을 이용한 알고리즘을 제시하였으며, 사례연구를 통해 성능을 입증하였다.

• 한국공작기계학회논문집
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• 제15권5호
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• pp.14-20
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• 2006

In recent year, as the robot technology is developed, the researches on the artificial muscle actuator that enables robot to move dexterously like biological organ become active. Actuators are key technologies underpinning robotics. Breakthroughs in actuator technology, particular in terms of power-to-weight ratio, or energy-density, will have significant impacts upon the design and control of robotic system. In this paper, a new approach to design and control of shape memory alloy(SMA) actuator is presented to drive the robot hand. SMA wire is divided into many segments and their thermal states of the SMA are controlled individually in a binary manner. This control manner will reduce the hysteresis that the SMA material has and it becomes the fundamental technology to develop the anthropomorphic robot hand. In this paper, the mechanism In the digital step motor of the shape memory alloy that is driven by the segmented binary control, which is a new control technique, is studied. This SMA digital step actuator applies for the robot hand and the driving mechanism of the robot hand is investigated.

• 한국산학기술학회논문지
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• 제14권10호
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• pp.5105-5114
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• 2013

본 논문은 심해저 환경을 고려한 케이블 및 필터 설계에 관한 연구를 수행하였다. 심해저 플랜트에서 사용하고 있는 전기 아키텍처는 해상에서 고전압의 전원 공급 장치, 고용량 구동시스템, 장거리 케이블과 전동기로 구성되어있다. 전도 노이즈는 전동기 구동용 인버터의 고속 스위칭 시 발생하는 급속한 전압변화로 인해 발생하며, 케이블의 길이가 길어질수록 전동기에 심각한 과도 전압을 발생시킨다. 따라서 심해저 플랜트에 사용되는 장거리 케이블의 R, L, 선간 C, 선-접지 C를 고려한 선로를 설계하여 구동 전동기에 발생하는 과전압을 확인하였다. 또한, PWM 인버터 구동시스템의 전도 노이즈 저감을 위한 필터를 설계하여 심해저 플랜트 모델의 가이드라인을 제안하고자 한다.

• 전자공학회논문지SC
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• 제44권1호
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• pp.12-18
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• 2007

본 연구에서 설계한 AFCI는 Arc 고장 차단기로서 종속된 전기 배선상의 노화, 절연 및 배선 파괴, 연결 고장, 절연과 배선에 과도한 기계적 손상으로 인한 아크고장을 검출하여 차단하는 기능을 가지고 있으며 기존 차단기가 가지고 있던 과전류에 의한 바이메탈의 만곡 특성에 의한 동작으로 차단하는 방식은 차단에 긴 시간이 걸리나 설계한 AFCI는 전자방식으로서 과부하, 과전류에 의한 기계적 , 전기적인 스트레스를 검출하여 차단하는 기능을 가진 제품으로 차단시간이 100% 이상 단축되어 전기 화재의 발생률을 낮추도록 하였다.

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.126-133
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• 2017

This paper deals with the effects of welding, which is done to fix the stator stack, on a motor in case of fabricating a prototype motor that is manufactured in a small quantity. In the case of a small motor, the stator is designed and fabricated with the segmented core as a way to raise the fill factor of winding wire to the utmost within a limited size. In case of fabrication by welding both inside and outside of the stator in order to fix the segmented-core stator, the effects of stack are ignored, and the eddy current loss occurs. This paper performed the no-load test on an IPM-type BLDC motor for driving the suction fan of a vacuum cleaner, which was manufactured by using a segmented-core stator. As a result of the test, it was found that input power more than expected was supplied. To analyze the effects of welding by using the finite element analysis method and verify them experimentally, a stator was re-manufactured by bonding, and input power supplied during the no-load test was compared.

• 전기학회논문지
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• 제67권5호
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• pp.644-650
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• 2018

According to a miniaturization and integration of electric device, a little size of fuse satisfying the current carrying capacity as well as an explosive tolerance and current interrupt rating are required. Fe-Ni alloy is applied to decrease an oxidation of fuse elements. A resistance and T.C.R(temperature coefficient of resistance) of a fuse are analyzed by changing a content of Ni And full rated current I-T curve from 1A to 6.3A has been tested. In order to an explosive energy, a straight wire type is selected to reduce a fuse melting time. An interrupt rating test was conducted by changing a content of Ni and the optimal content of Ni is to be 40%.

• 한국대기환경학회지
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• 제31권2호
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• pp.118-130
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• 2015

Fine dust containing iron compounds is of current interests in metro subway as well as large scale industries including iron manufacturing and smelting works. This work attempts to find a new design of magnetic filter module for iron dust capture. It simulated the vertical rectangular duct with metal mesh which might promote electric fields in the duct space. A lab test using coal fly ash composed of 8.66% Fe with the most form of $Fe_3O_4$ and $Fe_2O_3$ showed capability of magnetic collection. It showed the capture efficiency with 80~93% for $PM_{2.5}$ depending on magnetic intensity. Ferromagnetic wire mesh contributed up to 50% of collection increment.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 추계 학술대회논문집
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• pp.177-180
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• 2004

The development of a tilting train with construction of electric line on the conventional railway is required for speed-up on the conventional railway with many curving sections. For development of tilting train, the study and development of the tilting system and tilting bogie having the different mechanism with a general high speed train will play a main role for improving the technology in the field of Korean railway The study and development of the pantograph tilting mechanism in order to keep a good contact behavior between a pantograph and a contact wire by tilting a pantograph on the opposite direction of the vehicle tilting direction. In this study, we analyzed the aerodynamic characteristic of a developing pantograph on the tilting train and obtained the contact force with catenary by aerodynamic lift force by the aerodynamic analysis. We also performed the numerical analysis for design the device controlling lift force on a pantograph. From the aerodynamic simulation and parameter study for a device to control the lift force, we will suggest the various shape and the optimal shape of it corresponding to a developing tilting pantograph. The Fluent software is used for the calculation of flow profile in this study.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.467-471
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• 2004

The development of a tilting train with construction of electric line on the conventional railway is required for speed-up on the conventional railway with many curving sections. For development of tilting train, the study and development of the tilting system and tilting bogie having the different mechanism with a general high speed train will play a main role for improving the technology in the field of Korean railway. The study and development of the pantograph tilting mechanism in order to keep a good contact behavior between a pantograph and a contact wire by tilting a pantograph on the opposite direction of the vehicle tilting direction. In this study, we analyzed the aerodynamic characteristic of a developing pantograph on the tilting train and obtained the contact force with catenary by aerodynamic lift force by the aerodynamic analysis. We also performed the numerical analysis for design the device controlling lift force on a pantograph. From the aerodynamic simulation and parameter study for a device to control the lift force, we will suggest the various shape and the optimal shape of it corresponding to a developing tilting pantograph. The Fluent software is used for the calculation of flow profile in this study.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.535-538
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• 2004

Superconducting transmission power cable is one of interesting parts in power application using high temperature superconducting wire. One of important parameters in high-temperature superconduting (HTSC) cable design is transport current distribution because it is related with current transmission capacity and AC loss. In this paper, the transport current distribution at conducting layers was investigated through the analysis of the equivalent circuit for HTSC power cable with shield layer and compared with the case of without shield layer. The transport current distribution due to the pitch lenght was improved in the case of HTSC power cable with shield layer from the analysis.