• 제목/요약/키워드: Power characterization

검색결과 740건 처리시간 0.033초

테라헤르츠 전자기 펄스를 이용한 이산화규소의 전기적 광학적 특성 (The Electrical and Optical Characteristics of Silica Sand by Terahertz Electromagnetic Pulses)

  • 전태인
    • 한국전기전자재료학회논문지
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    • 제14권3호
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    • pp.202-206
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    • 2001
  • Using THz time-domain spectroscopy (THz-TDS), the power absorption, the index of refraction, and the real conductivity of silica sand are measured from 0.1[Thz] to 0.5[Thz] frequency range. It is impossible to measure the characterization of the silica sand by simple electrical measurements using mechanical contacts, e.g., Hall effect or four-point probe measurements. However, the THz-TDS technique can measure not only electrical but also optical characterization of he sample. Also this technique can measure frequency dependent results. Especially, the real conductivity was increased according to THz frequency. This is unusual material compare with metal and semiconductor materials; the measured real conductivity are not followed by the simple Drude theory.

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방사선조사에 따른 원전 저압케이블용 절연재료의 특성분석 (Characterization of Insulation Materials for Low Voltage Cables in a Nuclear Power Plant with ${\gamma}$-Ray Irradiation)

  • 박정기;이우선;한재홍
    • 한국전기전자재료학회논문지
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    • 제14권5호
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    • pp.397-404
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    • 2001
  • This study describes the effect of γ-ray irradiation on the properties of insulation materials for low voltage cables in a nuclear power plant. The radiation effects were characterized by measuring OIT, FTIR, electrical properties of the irradiated specimens. As a result, they showed the decrease of OIT and the increase of chemical structural defects with the increase of γ-ray amount. Also, the electrical properties such as dielectrical constant, tan $\delta$ and current were changed by aging. These changes may come from the increase of chemical structural defects by $\delta$-ray irradiation.

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지중배전 케이블의 노화에 의한 가교도 특성 (Crosslinked Characteristics of XLPE Cables by Aging)

  • 이우선;조준호;최권우;정창수;정용호;김상용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.1566-1568
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    • 2000
  • This study refers to the crosslinked characteristics of XLPE cables by aging. The cable failure brings about an enormous loss of power supply and the immense expense for cable replacement. These characterization techniques can be used for identifying a cause of failure and for improving a quality of equipments Also, these play an important role in the detection of premature failure. In order to maintain a cable reliability, quality control is needed strictly. It can be possible to estimate a residual lifetime of power cable using characterization techniques.

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Characterization and Performance Evaluation of Advanced Aircraft Electric Power Systems

  • Eid, Ahmad;El-Kishky, Hassan;Abdel-Salam, Mazen;El-Mohandes, Mohamed T.
    • Journal of Power Electronics
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    • 제10권5호
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    • pp.563-571
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    • 2010
  • A model of an advanced aircraft electric power system is developed and studied under variable-speed constant-frequency (VSCF) operation. The frequency of the generator's output voltage is varied from 400-Hz to 800-Hz for different loading scenarios. Power conversions are obtained using 12-pulse power converters. To reduce the harmonic contents of the generator output waveforms, two high-pass passive filters are designed and installed one at a time at the generator terminals. The performance of the two passive filters is compared according to their losses and effectiveness. The power quality characteristics of the studied VSCF aircraft electric power system are presented and the effectiveness of the proposed filter is demonstrated through compliance with the newly published aircraft electrical standards MIL-STD-704F.

LCA를 통한 국내 발전기술의 글로벌 환경성 평가 (Global Environmental Impacts Assessment of Power Generation Technologies with LCA Method)

  • 정환삼;김성호;김태운
    • 에너지공학
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    • 제14권2호
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    • pp.140-146
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    • 2005
  • 이 연구에서는 전과정평가 방법을 토대로 국내 가동중인 대표적 발전기술들의 글로벌 환경성을 평가하였다. 전과정평가 방법론은 환경영향을 평가하는데 있어 유용성이 뛰어난 도구이다. 대표적 발전원들은 국내 전력공급의 $90\%$ 정도를 차지하고 있는 원자력, 유연탄, LNC 발전소로 하였고, 여기에 더하여 재생 에너지원 중 대표 격인 풍력발전 기술로 하였다. 환경영향 평가는 지구 지역, 부지의 환경에 영향을 미치는 8개의 영향범주를 설정한 후, 발전원별 환경영향을 평가하기 위해 특성화 영향 지표를 계산하였고, 영향범주간 상대적 중요성을 비교하기 위해 정규화 영향 지표도 평가되었다.