• Title/Summary/Keyword: 전극봉

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동판접지전극과 동선접지전극사용에 대한 기술적 및 경제적 비교

  • 조건찬
    • 전기의세계
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    • v.11
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    • pp.56-61
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    • 1963
  • 현재 우리나라에서 사용하고 있는 접지전극은 30*30$cm^{2}$의 넓이와 0.7,0.9,1.0,2.0mm의 동판전극들이다. 인건비가 비싸고 전극 자료비가 우리나라에 비하여 싼 외국에서는 접지봉을 많이 사용하고 있다. 접지봉을 사용하면 인건비는 적게들지만 매설하기 위한 기계의 시설비와 같은 접지저항치를 얻기 위한 동량이 판전극 사용시보다 더욱 많이 필요하므로 우리나라 현사정에는 부적당하다. 본 연구의 목적은 소요접지저항을 얻는데 동판전극보다 더욱 경제적인 접지방식을 모색하여 이것과 동판전극방식과의 기술적, 경제적비교검토를 하는데 있다.

A Study of Multi-channel AFS for Marine Traffic Facilities (해양교통시설물용 다채널 AFS에 관한 연구)

  • Kim, Ji-Yoon;Lee, Ji-Young;Oh, Jin-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.1
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    • pp.75-80
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    • 2015
  • After some period of time, the marine traffic facilities find problems caused by shellfish adhered to inside and inlet of the water column. Therefore, single-channel AFS(Anti-Fouling System) has been applied in order to minimize the deposition of shellfish. However, imbalance phenomenon of ionization of copper electrodes that are used for single-channel AFS appeared. This problem resulted in frequent replacement of anode. In this paper, multi-channel current control system has been developed, as well as the related hardware has been designed and fabricated. Further, experimental study has been undertaken to compare the application of single and multi- channel AFS. Through the sea experiments, it was possible to confirm that the copper electrode used for multi-channel AFS is uniformly ionized.

A Study on Micro-Hole Drilling by EDM (미세구멍의 방전가공에 관한 연구)

  • 윤재웅;양민양
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.5
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    • pp.1147-1154
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    • 1990
  • Micro-hole drilling by EDM and production of fine rods for the tool electrode or other purpose have become very important in industry. This paper suggests a new method for production of very fine rods by ultrasonic-assisted chemical machining and describes the machining characteristics of micro-hole drilling by EDM. For fine rods, copper wires of initial diameter of 250.mum are used and successfully machined into a diameter of less than 30.mum with good repeatability. The ultrasonic agitation not only accelerated the material removal rate uniformly, but also produced smooth surfaces of fine rods. To drill the micro-hole, kerosene and pure water is used as a dielectric. From the experiment, water is superior to kerosene with respect to surface roughness of inlet and outlet of hole and machined surface as well as electrode wear. However, due to the electrochemical reaction of water, small pits are remained on the workpiece surface.

Behaviors of Impulse Ground Impedances Associated with the Current Injection Point in a Ground Rod (봉상 접지전극에시 전류유입위치에 따른 임펄스 접지임피던스의 특성)

  • Lee, Bok-Hee;Jeong, Dong-Cheol;Lee, Su-Bong
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.1
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    • pp.94-100
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    • 2005
  • This paper presents the behaviors of transient and effective impulse impedances of a long ground rod associated with the current injection points. The laboratory test for the time domain performance of actual-sized model ground rod subjected to a lightning stroke current has been carried out The transient ground impedances of long ground rods under impulse currents were higher than the ground resistance. Both of the ground resistance and the effective impulse ground impedance decrease with increasing the length of the ground rods. Also, the effective impulse ground impedances are significantly increased in fast rise time ranges. The reduction of the ground resistance is decisive to improve the impulse impedance characteristics of grounding systems. When the test current is injected at the bottom of ground rod, the oscillating pulses with high frequency are included on the wave front of ground rod potential and the effective impulse impedances are higher than any other cases.

고온 용융염에 활용 가능한 Ag/AgCl 기준전극 제조 및 이를 이용한 Cd 액체음극에서의 란탄족 염화물의 순환 전압 전류 특성

  • 안병길;심준보;김응호;유재형
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.333-333
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    • 2004
  • 고온의 용융염 매질에서 전해 정련 또는 전해제련에 의해 원하는 물질을 회수하기 위한 공정에 있어서 정확한 산화/환원 전위 측정 및 안정된 전위를 인가하기 위해서는 재현성과 내구성이 확보된 기준 전극이 필요하다. 용융염 매질에서 많이 사용되는 기준 전극은 Ag/AgCl 전극으로서 온도 사이클에 대한 전위의 히스테리시스가 작고 고온에서도 전위가 안정하다. Ag/AgCl 기준전극으로 pyrex 봉 하단부를 수 마이크론 두께의 pyrex 박막으로 제작된 것은 고온 용융염에 접촉시 열 충격, 전극류와 충돌에 의한 물리적 취약성 및 고온의 용융염에 의한 부식과 같은 단점이 있다.(중략)

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Impulse Ground Impedances of a Deeply Driven Ground Rod Combined with Different Shape Grounding Electrodes (형상이 다른 접지전극에 접속된 심매설 봉상 접지전극의 임펄스접지임피던스 특성)

  • Lee, Bok-Hee;Lee, Su-Bong;Chang, Keun-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.2
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    • pp.63-68
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    • 2005
  • This paper describes the characteristics of effective impulse ground impedance of deeply driven ground rods combined with grounding grid or counterpoises with needles. The potential rises of the test ground electrodes were measured as a function of the rise time of applied impulse currents and the effective impulse ground impedances were calculated The impulse ground impedances of deeply driven ground rods strongly depend on the rise time of impulse currents and significantly reduced by the connection of grounding grids in parallel.