The danger of water trees in polymer insulated power cables evaluated from calculations of electric field in the presence of water trees of different shapes and permittivity distributions

Journal of Electrostatics (Impact Factor: 1.27). 06/1997; DOI: 10.1016/S0304-3886(97)00066-1

ABSTRACT From the assumption that water trees influence the AC electric field distribution in the insulation due to their permittivity higher than that of the surrounding medium, calculations of electric field in the vicinity of model water trees are presented. The electric field is locally amplified and reaches values high enough to be considered as a danger for the cables.

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