• Title/Summary/Keyword: Electric Wires

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A Study to Identify the Causes of Electrical Fires (전기화재의 원인감식에 관한연구)

  • 박남신;김상렬;김찬오;이재인
    • Journal of the Korean Society of Safety
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    • v.7 no.3
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    • pp.89-98
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    • 1992
  • In this study, the methods to identify the causes of electrical fires are suggested. Among several causes of electrocal fires, it is focused upon a short-circuit and an over-current accidents, which take the highest ratio compare with any other causes. To propose the exact method of identification, electric wires(HIV, IV), fuses and plug-receptacls are tested under the conditions of electrical accidents and external fires, respectively. By analyzing the microphotographs, the differences between the results from electrical fires and the others are found out.

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A Study on the efficiency test of Electric Discharge Machine Wire using Image processing (화상처리를 이용한 방전와이어의 성능평가에 대한 연구)

  • 배진한;이위로;유송민
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.10a
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    • pp.117-122
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    • 2002
  • Electrical discharge machining uses thermal energy from electrical discharge, while wire electrical discharge machining (WEDM) technology is widely used in conductive material machining. This paper proposes a method for evaluating the characteristics of wires in WEDM. In order to evaluate the wire processing performance, processing speed and roughness, straightness, corner processing have been assessed with precision experiment equipment and image processing including Laplacian filtering with various threshold levels.

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A Study on the Electric Railroad Grounding System of Tunnels and Bridges (전기철도 시스템에서의 터널, 교량구간 접지방안 연구)

  • 윤응규;오광해;오기봉
    • Proceedings of the KSR Conference
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    • 2002.10a
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    • pp.559-565
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    • 2002
  • This paper presents a standard grounding scheme for bridge and tunnel areas where earthing wires cannot be easily buried. Specially, a new grounding method in which structure grounding devices are used shows good grounding effects like the earthing-wire grounding scheme. The proposed method can be a measure for equal potential in case earthing cables are disconnected.

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Surge Protection methods in Railway Signalling system (이상전압으로부터 철도신호설비 보호방안 고찰)

  • Cho, B.K.;Lee, J.H.
    • Proceedings of the KIEE Conference
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    • 2001.10a
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    • pp.285-288
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    • 2001
  • The Railway Signalling Equipment's transformation to Micro-electronic has been caused to the decrease of its introspection against a surge voltage. So, there has been many tries to protect the railway signalling equipment from a surge voltage by using of a various surge protector. In this study, we are trying to draw up the protective plan to prevent this weakness on introspection by analyzing the electric characteristic on such a surge protector and reviewing the way on distributing wires in signalling room.

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A Study for Fault Location Scheme Using the 9-Conductor Modeling of Korean Electric Railway System (9도체 전기철도 모델링을 이용한 고장점 표정 방안 연구)

  • Lee, Han-Sang;Lee, Chang-Mu;Lee, Han-Min;Jang, Gil-Soo;Chang, Sang-Hoon
    • Proceedings of the KIEE Conference
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    • 2006.11a
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    • pp.411-413
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    • 2006
  • This paper presents a novel fault location scheme on Korean AC electric railway systems. On AC railway system, because there is a long distance, 40 km or longer, between two railway substations, a fault location technique is very important. Since the fault current flows through the catenary system, the catenary system must be modeled exactly to analyze fault current magnitude and fault location. In this paper, before suggestion for the novel scheme of fault location, a 9-conductor modeling technique that includes boost wires and impedance bonds is introduced, based on the characteristics of Korean AC electric railway. After obtaining a 9-conductor modeling, the railway system is constructed for computer simulation by using PSCAD/EMTDC. By case studies, we can verify superiority of a new fault location scheme and suggest a powerful model for fault analysis on electric railway systems.

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Development of Temperature Control Technology of Root Zone using Multi-line Heating Methods in the Strawberry Hydroponics (다선식 가온방식을 이용한 딸기 수경재배의 배지 온도조절 기술 개발)

  • Kim, Ki-Dong;Ha, Yu-Shin;Lee, Ki-Myung;Park, Dae-Heum;Kwon, Soon-Hong;Choi, Won-Sik;Chung, Sung-Won
    • Journal of Bio-Environment Control
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    • v.19 no.4
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    • pp.189-194
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    • 2010
  • A multi line electric tube consisted of XL pipes contained with 2~4 hot wires and water in it. The specification of one meter length multi-line electric tube was investigated and the proper number in the multi-line electric tube was determined. A multi line electric tube with three hot wires were found to be the most efficient for the media heating control system. Temperature rise of medium in the rice hulls media was faster than that in the perlite media, showed better insulation effect of rice hulls media. Temperature rise of medium with mulching on the top of the bed was faster than without mulching, resulted in the beneficial effect of temperature rise with mulching. The regression model for the rice hulls media with mulching air temperature of $5^{\circ}C$ were a = -0.1458 and b = -0.1088. Using the model, the temperature rise of medium during low temperature season can be predicted for the various media according to the different depths.

Development of Integrated Composite Suspension wire with Optical Fiber (일체형 광섬유복합조가선(OPSW) 개발 구축)

  • Sone, Young-Cher;Choi, Hyun-Beom;Kim, Byung-Jik;Kim, Young-Tak;Yun, Kyoung-Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1122-1127
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    • 2011
  • The thesis here by shows that the extant suspension wire, which is stretched between electric poles to support a variety of communication wires, can be replaced by specially-redesigned cables called OPSW(Composite Suspension Wire with Optical Fiber) which have been devised for the first time in the world so that the functions of both communication and support can be united into one cable which is sure to be successfully installed on site, hence leading to outstanding effects that it can sharply reduce the load applied to electric poles as well as the cost of forthcoming constructions and that it can accordingly make a great contribution to the building of Smart Grid network.

Practical Methodology of the Integrated Design and Power Control Unit for SHEV with Multiple Power Sources

  • Lee, Seongjun;Kim, Jonghoon
    • Journal of Electrical Engineering and Technology
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    • v.11 no.2
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    • pp.353-360
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    • 2016
  • Series hybrid electric vehicles (SHEVs) having multiple power sources such as an engine- generator (EnGen), a battery, and an ultra-capacitor require a power control unit with high power density and reliable control operation. However, manufacturing using separate individual power converters has the disadvantage of low power density and requires a large number of power and signal cable wires. It is also difficult to implement the optimal power distribution and fault management algorithm because of the communication delay between the units. In order to address these concerns, this approach presents a design methodology and a power control algorithm of an integrated power converter for the SHEVs powered by multiple power sources. In this work, the design methodology of the integrated power control unit (IPCU) is firstly elaborately described, and then efficient and reliable power distribution algorithms are proposed. The design works are verified with product-level and vehicle-level performance experiments on a 10-ton SHEV.

Electrical Strength of the Insulating Materials for High-Tc Superconducting Devices

  • Bae, Duck-Kweon;Kim, Chung-Hyeok;Oh, Yong-Cheul;Kim, Jin-Sa;Shin, Cheol-Gee;Song, Min-Jong;Lee, Joon-Ung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.149-150
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    • 2005
  • According to the trend for electric power equipment of high capacity and reduction of its size, the needs for the new high performance electric equipments become more and more important. On of the possible solution is high temperature superconducting (HTS) power application. Following the successful development of practical HTS wires, there have been renewed activities in developing superconducting power equipment. HTS equipments have to be operated in a coolant such as liquid nitrogen ($LN_2$) or cooled by conduction-cooling method such as using Gifford-McMahon (G-M) cryocooler to maintain the temperature below critical level. In this paper, the dielectric strength of unfilled epoxy and filled epoxy in $LN_2$ was analyzed. The filled epoxy composite not only compensates for this fragile property but enhances its dielectric strength.

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The Aqueous Corrosion Characteristics of Catenary Materials of Electric Railway System (전차선로 가선재의 수용액 부식 특성)

  • 김용기;장세기;조성일;이재봉
    • Journal of the Korean Society for Railway
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    • v.4 no.2
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    • pp.62-70
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    • 2001
  • Pure copper, Cu-1.1wt%Cd and ACSR(Aluminum Conductor Steel Reinforced) have been used as catenary materials of the electric railway system. Since these materials may be exposed to the corrosive environments like polluted air, acid rain and sea water, it is important to investigate the corrosion rates in various corrosive environments. The aqueous corrosion characteristics of catenary materials in aerated acid, neutral and alkali solutions were studied by using immersion corrosion tests, electrochemical measurements and analytical techniques. In order to examine corrosion characteristics according to the dissolved oxygen content, pH, chloride ion concentration ion, and the addition of Cd to Cu, a series of tests such as potentiodynamic polarization, a.c impedance spectroscopy and galvanic corrosion tests were carried out with these materials. Results showed that the addition of Cd to Cu and chloride ion in the solution have an adverse effects on the resistance to corrosion. Additionally, Galvanic currents between Al and steel wires of ACSR were confirmed by using ZRA(zero resistance ammeter) method.

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