| Project/Area Number |
14550262
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
電力工学・電気機器工学
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| Research Institution | Gifu University |
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Principal Investigator |
TAKAGI Nobuyuki Gifu University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (80179415)
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| Co-Investigator(Kenkyū-buntansha) |
WATANABE Teiji Gifu University, Faculty of Engineering, Professor, 工学部, 教授 (20021595)
WANG Daohong Gifu University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (20273120)
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| Project Period (FY) |
2002 – 2004
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| Project Status |
Completed (Fiscal Year 2004)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2004: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2003: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2002: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | space charge density / thundercloud / sound wave / lightning protection / real time sensing |
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| Research Abstract |
In this study, our final goal is to make clear the relationship between the failure of lightning shield and the space charge around power line towers. To succeed this purpose, we have done three studies, 1.space charge measurement by new supersensitive system using sound wave, 2.effect of wind on the corona discharge current from a needle, 3.high speed video of upward lightning leader stroke.
In the study 1., we estimated the position and the density of the space charge charged in water vapor with errors of 1% to 14% and 10% and 77%, respectively. The charge density over needles mounted on a pipe with 14.5m high under thundercloud is about 100nC/m3.
In the study 2., we found out that the corona discharge current from a needle increases with the wind speed, but decreases with the wind speed when there is an another needle in the windward.
In the study 3., the speed of the upward leader stroke increases with height. And some small discharges occur associated with leader progress.
From above the results, we concluded that the space charge have influences on the initiation and the progress of leader stroke from a tall tower under winter thundercloud.
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