Observation of water trees using terahertz spectroscopy and time-domain imaging

Ryo Sato, Marina Komatsu, Yoshimichi Ohki, Norikazu Fuse, Yoshinobu Nakamichi, Maya Mizuno, Kaori Fukunaga

    研究成果: Article

    19 引用 (Scopus)

    抄録

    Terahertz measurements were carried out to detect water trees grown in low-density polyethylene sheets. Water absorbs light at terahertz frequencies, fairly strongly at about 5.0 THz and rather weakly from 0.1 to 1.0 THz. Using the absorption at these frequencies, observation of water trees was tried according to the following procedures. First, we made a model sample, consisting of a polyethylene sheet, a water layer, and a copper plate, and terahertz light was irradiated to this sample vertically. The waveform and intensity of electric field of the terahertz light reflected by the sample clearly pointed out the presence of water layer beneath the polyethylene sheet by the reflection peak appearance time and the phase of reflected electric field. Secondly, water trees were grown in a polyethylene sheet, and terahertz light was scanned over the sheet. As a result, the intensity distribution of terahertz light reflected by the sample was in good agreement with the shape of the water trees. Observation of terahertz image was also carried out using the same polyethylene sheet with water trees over which a polyvinyl chloride sheet or a carbon-loaded polyethylene sheet was put to simulate the structure of a real cable. An image of water trees was also successfully observed. These results indicate that the terahertz spectroscopy can be a new characterization tool to observe the presence of water trees in a test sample taken from an aged cable.

    元の言語English
    記事番号6032826
    ページ(範囲)1570-1577
    ページ数8
    ジャーナルIEEE Transactions on Dielectrics and Electrical Insulation
    18
    発行部数5
    DOI
    出版物ステータスPublished - 2011 10

    Fingerprint

    Terahertz spectroscopy
    Imaging techniques
    Polyethylenes
    Water
    Cables
    Electric fields
    Low density polyethylenes
    Polyvinyl chlorides

    ASJC Scopus subject areas

    • Electrical and Electronic Engineering

    これを引用

    Observation of water trees using terahertz spectroscopy and time-domain imaging. / Sato, Ryo; Komatsu, Marina; Ohki, Yoshimichi; Fuse, Norikazu; Nakamichi, Yoshinobu; Mizuno, Maya; Fukunaga, Kaori.

    :: IEEE Transactions on Dielectrics and Electrical Insulation, 巻 18, 番号 5, 6032826, 10.2011, p. 1570-1577.

    研究成果: Article

    Sato, Ryo ; Komatsu, Marina ; Ohki, Yoshimichi ; Fuse, Norikazu ; Nakamichi, Yoshinobu ; Mizuno, Maya ; Fukunaga, Kaori. / Observation of water trees using terahertz spectroscopy and time-domain imaging. :: IEEE Transactions on Dielectrics and Electrical Insulation. 2011 ; 巻 18, 番号 5. pp. 1570-1577.
    @article{f194d5f93f0046b2b495fad3ffafc5b5,
    title = "Observation of water trees using terahertz spectroscopy and time-domain imaging",
    abstract = "Terahertz measurements were carried out to detect water trees grown in low-density polyethylene sheets. Water absorbs light at terahertz frequencies, fairly strongly at about 5.0 THz and rather weakly from 0.1 to 1.0 THz. Using the absorption at these frequencies, observation of water trees was tried according to the following procedures. First, we made a model sample, consisting of a polyethylene sheet, a water layer, and a copper plate, and terahertz light was irradiated to this sample vertically. The waveform and intensity of electric field of the terahertz light reflected by the sample clearly pointed out the presence of water layer beneath the polyethylene sheet by the reflection peak appearance time and the phase of reflected electric field. Secondly, water trees were grown in a polyethylene sheet, and terahertz light was scanned over the sheet. As a result, the intensity distribution of terahertz light reflected by the sample was in good agreement with the shape of the water trees. Observation of terahertz image was also carried out using the same polyethylene sheet with water trees over which a polyvinyl chloride sheet or a carbon-loaded polyethylene sheet was put to simulate the structure of a real cable. An image of water trees was also successfully observed. These results indicate that the terahertz spectroscopy can be a new characterization tool to observe the presence of water trees in a test sample taken from an aged cable.",
    keywords = "insulationdiagnosis, non-destructive analysis, terahertz imaging, Water tree",
    author = "Ryo Sato and Marina Komatsu and Yoshimichi Ohki and Norikazu Fuse and Yoshinobu Nakamichi and Maya Mizuno and Kaori Fukunaga",
    year = "2011",
    month = "10",
    doi = "10.1109/TDEI.2011.6032826",
    language = "English",
    volume = "18",
    pages = "1570--1577",
    journal = "IEEE Transactions on Dielectrics and Electrical Insulation",
    issn = "1070-9878",
    publisher = "Institute of Electrical and Electronics Engineers Inc.",
    number = "5",

    }

    TY - JOUR

    T1 - Observation of water trees using terahertz spectroscopy and time-domain imaging

    AU - Sato, Ryo

    AU - Komatsu, Marina

    AU - Ohki, Yoshimichi

    AU - Fuse, Norikazu

    AU - Nakamichi, Yoshinobu

    AU - Mizuno, Maya

    AU - Fukunaga, Kaori

    PY - 2011/10

    Y1 - 2011/10

    N2 - Terahertz measurements were carried out to detect water trees grown in low-density polyethylene sheets. Water absorbs light at terahertz frequencies, fairly strongly at about 5.0 THz and rather weakly from 0.1 to 1.0 THz. Using the absorption at these frequencies, observation of water trees was tried according to the following procedures. First, we made a model sample, consisting of a polyethylene sheet, a water layer, and a copper plate, and terahertz light was irradiated to this sample vertically. The waveform and intensity of electric field of the terahertz light reflected by the sample clearly pointed out the presence of water layer beneath the polyethylene sheet by the reflection peak appearance time and the phase of reflected electric field. Secondly, water trees were grown in a polyethylene sheet, and terahertz light was scanned over the sheet. As a result, the intensity distribution of terahertz light reflected by the sample was in good agreement with the shape of the water trees. Observation of terahertz image was also carried out using the same polyethylene sheet with water trees over which a polyvinyl chloride sheet or a carbon-loaded polyethylene sheet was put to simulate the structure of a real cable. An image of water trees was also successfully observed. These results indicate that the terahertz spectroscopy can be a new characterization tool to observe the presence of water trees in a test sample taken from an aged cable.

    AB - Terahertz measurements were carried out to detect water trees grown in low-density polyethylene sheets. Water absorbs light at terahertz frequencies, fairly strongly at about 5.0 THz and rather weakly from 0.1 to 1.0 THz. Using the absorption at these frequencies, observation of water trees was tried according to the following procedures. First, we made a model sample, consisting of a polyethylene sheet, a water layer, and a copper plate, and terahertz light was irradiated to this sample vertically. The waveform and intensity of electric field of the terahertz light reflected by the sample clearly pointed out the presence of water layer beneath the polyethylene sheet by the reflection peak appearance time and the phase of reflected electric field. Secondly, water trees were grown in a polyethylene sheet, and terahertz light was scanned over the sheet. As a result, the intensity distribution of terahertz light reflected by the sample was in good agreement with the shape of the water trees. Observation of terahertz image was also carried out using the same polyethylene sheet with water trees over which a polyvinyl chloride sheet or a carbon-loaded polyethylene sheet was put to simulate the structure of a real cable. An image of water trees was also successfully observed. These results indicate that the terahertz spectroscopy can be a new characterization tool to observe the presence of water trees in a test sample taken from an aged cable.

    KW - insulationdiagnosis

    KW - non-destructive analysis

    KW - terahertz imaging

    KW - Water tree

    UR - http://www.scopus.com/inward/record.url?scp=80054058894&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=80054058894&partnerID=8YFLogxK

    U2 - 10.1109/TDEI.2011.6032826

    DO - 10.1109/TDEI.2011.6032826

    M3 - Article

    AN - SCOPUS:80054058894

    VL - 18

    SP - 1570

    EP - 1577

    JO - IEEE Transactions on Dielectrics and Electrical Insulation

    JF - IEEE Transactions on Dielectrics and Electrical Insulation

    SN - 1070-9878

    IS - 5

    M1 - 6032826

    ER -