1993 Fiscal Year Final Research Report Summary
Study on Physico-mathematical Model of Dc Flashover Phenomena of Contaminated Insulators
| Project/Area Number |
04650235
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
電力工学
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| Research Institution | Nagoya Institute of Technology |
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Principal Investigator |
NAITO Katsuhiko Nagoya institute of Technology, Department of Electrical and Computer Engineering Professor, 工学部, 教授 (90240811)
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| Project Period (FY) |
1992 – 1993
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| Keywords | Dc Insulator / Physico-mathematical Model / Flashover / Contaminated Condition / Insoluble Material / Ambient Temperature / Pressure / Surface Wetting |
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| Research Abstract |
The purpose of this study is to construct a physico-mathematical model of de fiashover phenomena of contaminated insulators as well as to evaluate factors experimentally which affect flashover phenomena. The main results obtained during this study are as follows :
1. The results of worldwide round-robin artificial contamination test on dc high voltage insulators were analyzed. Improvement information which will serve for the revision of the existing international standard of dc contamination test.
2. Dc flashover phenomena are affected by the kinds of insoluble materials in the contaminant.
3. Ambient temperature and pressure have significant influence on dc flashover voltage.
4. Wetting condition on the insulator surface has to be considereded.
5. Analysis of leakage current waveforms obtained in dc contamination tests proved that waveforms depend on the shape and size of specimen and that relatively large current flows for about one second in some casess.
6. A model considering electrostatic capacitance was constructed in the case of ac voltage application. The calculated leakage current waveform based on the model is almost the same with the experimental one, suggesting the validity of the model.
7. Time variation of ac voltage distribution along series arrestors during the drying process of insulator surface was calculated by using a newly constructed model. It was shown that unusual voltage distribution 1.8 times as large as the normal may was obtained in a typical case.
Construction of a physico-mathematical model in the case of dc voltage application is now in progress.
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