• Title/Summary/Keyword: Leakage energy

Search Result 722, Processing Time 0.038 seconds

Investigation of Recovery Characteristic in Silicone Rubber Used for Outdoor Insulation by Measuring Leakage Current (누설전류 측정을 통한 옥외용 실리콘 절연재의 회복특성)

  • Huh, Chang-Su;Youn, Bok-Hee;Lee, Sang-Youb;Lee, Jong-Han
    • Proceedings of the KIEE Conference
    • /
    • 1999.07d
    • /
    • pp.1605-1607
    • /
    • 1999
  • Silicone rubber have presently been using in large number for a variety of outdoor HV applications. Silicone rubber have the properties of low surface energy and are able to retain its hydrophobicity or water repellency, thereby suppress the leakage current in the present of moisture and contamination. In this paper, we investigated the recovery characteristics of silicone rubber by measuring the leakage current under salt-fog.

  • PDF

Failure Examples for Parasitic Current Leakage of Starting System in Automotive (자동차 시동시스템의 암전류 누설에 의한 고장사례연구)

  • Lee, Il-Kwon;Kim, Chung-Kyun;Cho, Seung-Hyun
    • Tribology and Lubricants
    • /
    • v.26 no.5
    • /
    • pp.277-282
    • /
    • 2010
  • The purpose of this paper is to study and analysis the failure examples for parasitic current leakage produced in starting system on gasoline engine. It verified the discharge of battery by electric leakage because of internal wiring damage problem for CD auto changer installed in car. Also, it verified the no-stating phenomenon because of deposit forming by chemical reaction of battery fluid between battery post and cable fixing parts. It verified the damage for brush holder and commutator mixing by internal short phenomenon because of brush carbon a particle and engine oil that was flowed into internal of starting motor. It verified the working phenomenon of audio by a point of contact even if the driver turn to "LOCK" position the key.

3-D Analysis of Leakage Impedances in a 1MVA HTS Transformer (1MVA고온초전도 변압기의 3차원 누설임피던스 해석)

  • 김성훈;김우석;최경달;주형길;홍계원;한진호;한송엽
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2003.02a
    • /
    • pp.200-202
    • /
    • 2003
  • In this paper, 3-D electromagnetic analysis of a single phase 1MVA 22.9kV/6.6kV High Temperature Superconducting(HTS) transformer with double pancake windings by using the OPERA 3D was accomplished. And in order to perform the analysis of leakage impedances of a 1MVA HTS transformer, the energy conservation method was used. The efficiency voltage regulation and % impedance voltage drop of a 1MVA HTS transformer were obtained by the analysis of leakage impedances.

  • PDF

I-V Characteristics of SrTiO$_3$ Ceramics Capacitor Thin Films. (SrTi0$_3$세라믹 캐패시터 박막의 I-V 특성)

  • 이우선;김남오;정용호;이경섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1996.11a
    • /
    • pp.79-81
    • /
    • 1996
  • We fabricated SrTiO$_3$thin film capacitor on the Ag/Si-wafer by RF sputtering deposition. And I-V characteristics and structual analysis of the thin film capacitor are investigated. We found that the leakage current of the films during deposition is strongly denpent on the ambient gas and substrate temperature. Because of increase of activation energy, leakage current increased at high temperature and resistivity of the films was decreased. According to the increase of oxygen gas flow rate, the conductivity of thin film capacitor was increased and leakage current was decreased.

  • PDF

A Study on the Deterioration Progress of Railway Arresters (철도용 피뢰기의 열화진전에 관한 연구)

  • 길경석;한주섭;한문섭
    • Journal of the Korean Society for Railway
    • /
    • v.7 no.4
    • /
    • pp.307-311
    • /
    • 2004
  • Arresters are the best protective device on electrical power systems against transient overvoltages generated by lightning and/or switching operation. Nonetheless, arresters are deteriorated by absorption of moisture in the environments of its use, repetition in the protective operation to overvoltages, and some defects at manufacturing. It is therefore important to estimate the electrical characteristic changes of ZnO blocks. In this paper, an accelerated ageing test by a standard lightning impulse current was carried out to extract parameters needed for arrester diagnosis, and leakage current components were measured. Total energy applied to the ZnO blocks at each time is about 1,050[J] in 8/20[${\mu}\textrm{s}$] impulse current. From the experimental results, we proposed electrical parameters and leakage current level to diagnose arrester soundness.

A Contactless Energy Transfer Circuit Using Coreless Low-profile PCB Transformer (코어없는 초박형 PCB 변압기를 이용한 무접점 전력변환 회로)

  • 최병조
    • Proceedings of the KIPE Conference
    • /
    • 2000.07a
    • /
    • pp.505-508
    • /
    • 2000
  • A coreless printed circuit board(PCB) transformer is employed in a contactless energy transfer circuit that achieves an efficient power conversion at the presence of a considerable airgap between the source and the load side. A half-bridge series resonant converter is selected as the contactless energy transfer circuit in order to minimize the detrimental effects of large leakage inductance small magnetizing inductance and poor coupling coefficient of the coreless PCB transformer. The operation and performance of the proposed contactless power converter are verified on a 7 W experimental circuit that provides an 18V/0.4A output from a 210-370 V input source.

  • PDF

Removal of Interface State Density of SiO2/Si Structure by Nitric Acid Oxidation Method (질산산화법을 이용한 SiO2/Si 구조의 계면결함 제거)

  • Choi, Jaeyoung;Kim, Doyeon;Kim, Woo-Byoung
    • Korean Journal of Materials Research
    • /
    • v.28 no.2
    • /
    • pp.118-123
    • /
    • 2018
  • 5 nm-thick $SiO_2$ layers formed by plasma-enhanced chemical vapor deposition (PECVD) are densified to improve the electrical and interface properties by using nitric acid oxidation of Si (NAOS) method at a low temperature of $121^{\circ}C$. The physical and electrical properties are clearly investigated according to NAOS times and post-metallization annealing (PMA) at $250^{\circ}C$ for 10 min in 5 vol% hydrogen atmosphere. The leakage current density is significantly decreased about three orders of magnitude from $3.110{\times}10^{-5}A/cm^2$ after NAOS 5 hours with PMA treatment, although the $SiO_2$ layers are not changed. These dramatically decreases of leakage current density are resulted from improvement of the interface properties. Concentration of suboxide species ($Si^{1+}$, $Si^{2+}$ and $Si^{3+}$) in $SiO_x$ transition layers as well as the interface state density ($D_{it}$) in $SiO_2/Si$ interface region are critically decreased about 1/3 and one order of magnitude, respectively. The decrease in leakage current density is attributed to improvement of interface properties though chemical method of NAOS with PMA treatment which can perform the oxidation and remove the OH species and dangling bond.

A Review on Past Cases of Self-potential Surveys for Dikes and Embankments Considering Streaming Potential (흐름 전위 특성을 고려한 수리시설물에서의 자연 전위 탐사 사례 고찰)

  • Song, Seo Young;Cho, AHyun;Kang, Peter K.;Nam, Myung Jin
    • Journal of Soil and Groundwater Environment
    • /
    • v.26 no.6
    • /
    • pp.1-17
    • /
    • 2021
  • Self-potential (SP) surveys measure naturally occurring differences in electrical potential in the absence of artificial sources and have been applied to various fields since the first application in mineral explorations. Among various causes of SP occurrences, streaming potential is generated by the flow of groundwater, and makes SP surveys suitable for the exploration of groundwater table fluctuation, fractures, sinkholes and landslide occurrences. Recently, there has been many studies that applied SP surveys to monitor water leakage through dikes and embankments. In this review paper, we first review the characteristics and theoretical backgrounds of streaming potential in saturated or unsaturated porous media to introduce it in the embankment among various application field. After the review of the background theory, we review the past cases of field SP surveys on dikes and embankments and also the characteristics of field streaming potential data in the surveys. Further, by analyzing past studies of qualitative as well as quantitative interpretation of SP survey data, we show the possibility of quantitative interpretation of streaming potential data obtained on dikes and embankments. Consequently, it is hope that this review paper helps researches on SP surveys on dikes and embankments, and provides basis for interpretation methods of the SP data to identify leaked area and further leakage rate (or permeability).