• 한국전자통신학회논문지
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• 제6권5호
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• pp.643-648
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• 2011

본 연구에서는 공항, 철도, 항만 등 대형 교통수단의 표시등으로 사용하기 위하여 SMPS에 의하여 구동되는 LED 신호등을 설계하고 제작된 LED 신호등의 전기적 특성과 EMI 특성을 조사하였다. 10V 이상의 교류 및 직류입력전압에 대한 출력전류는 1.67A이었다. 0.15~30MHz에서 측정한 잡음단자전압은 허용기준 준첨두치와 허용기준 평균치 보다 낮았으며, 30~1000MHz에서 측정한 잡음전계강도는 59.96MHz에서 $23.96dB{\mu}V/m$이었다.

• 전기학회논문지
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• 제65권3호
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• pp.511-519
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• 2016

This paper is proposed control algorithm for the using thyristor of the parallel dual converter for Urban railway power supply in order to return the regenerative power generated by regenerative braking in urban railway train. Conventional control algorithm of Thyristor dual converter for urban railway power supply has voltage variation within a control range of hysteresis band. The purposed control algorithm of the parallel thyristor dual converter is to maintain a constant voltage without voltage variation in accordance with variable load through the Sequential mode change. And the control algorithm need calculating optimum initial firing angle to consider magnitude of the load current slope. For this purpose, Proposed algorithm for sequential conversion mode of the dual converter was verified by applying for the simulation.

• 전기학회논문지
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• 제61권12호
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• pp.1964-1969
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• 2012

This paper presents to verify the selective grounding fault protective relaying technique for the ungrounded DC traction power supply system. This system selectively blocks fault section when grounding fault occurred. In order to perform this verification, field test facilities have been installed on Oesam substation and Worldcup-Stadium substation, and field test process has been suggested. Also, selective grounding fault protective relaying components and rail voltage reduction device have been tested with the various trial examinations. In order to compare and evaluate performance of the selective grounding fault protective relaying function, field test system was modeled and the system fault simulation results were compared and evaluated with the field test result. Performance of selective grounding fault protective relaying function was evaluated with the above-mentioned process, and the fact that the system recognizes fault section irrespective of insulation between rail and ground and fault resistance from grounding fault.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.273-275
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• 2005

The national need to establish a new stray current mitigation method to protect the underground metallic infrastructures in congested downtown area forced us to design and develop the distributed impressed current cathodic protection (DICCP) system. The main purpose of this system is to replace the stray current drainage bond methods, which is widely adopted by pipeline owners in Korea. Currently, forced drainage makes up about 85% of total drainage facilities installed in Korea because polarized drainage can neither drain perfectly the stray currents during normal operation of electric vehicle nor drain the reverse current during regenerative braking at all. The forced drainage, however, has been abused as an alternative cathodic protection system, which impresses currents from rails to the pipelines and accordingly uses the rails as anodes. As a result, it is necessary to consider a new method to both cathodically protect the pipelines and effectively drain the stray currents. In this paper, we describe the design parameters and installation schemes of DICCP system that can meet these demands.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.276-278
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• 2005

For over 25 years, the stray currents from DC electric railroads have caused serious interference problems with underground metallic infrastructures in Korea. The most serious interference is reported at the pipelines near the depot areas. Our field survey proves that this phenomena is mainly due to the missing of dedicated rectifiers for mainline, depot and/or workshop areas. Because it takes so much time and costs too much to replace the traction power system, we consider a stray current confinement method which collects the stray currents and drains them to the negative terminal of the rectifier. This can be realized by installing a stray current collecting wire along the depot boundary. Moreover, we found the stray current collecting reinforcement bar located beneath the rails of concrete slab tracks. Using this bar, we arc going to draing the stray currents from mainline rails. In this paper we show the result of field survey on railroad facilities and present the stray current confinement method under field test.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1601-1603
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• 2005

현재 국내에서의 견인전동기 개발현황은 직류전동기는 655kW, 교류전동기는 210kW정도이며, 주행속도가 200km/h이상인 고속에 적용되는 1,000 kW급 이상 유도전동기 기술은 한국형 고속전철이 국내에서는 최초이다. 최고 주행속도 300km/h급의 고속전철용 1,130kW 동기전동기에 대한 제작 및 시험기술만을 프랑스에서 이전 받아 유도전동기를 제작하였다. 고속철도 차량용 견인전동기는 한정된 공간에 취부되어야 함으로 경량화가 필수적이다. 또한 전력기기에 대한 에너지 고밀도화가 가능해야 함으로 열적 특성에 대한 분석이 체계적으로 이루어져야 한다. 본 연구를 통해 외기 온도, 주행 속도 및 운행 시간에 따른 견인전동기의 온도 특성변화를 살펴봄으로써 고속전철용 견인전동기의 고정자 온도 특성을 확인할 수 있었다.