INIFTA   05425
INSTITUTO DE INVESTIGACIONES FISICO-QUIMICAS TEORICAS Y APLICADAS
Unidad Ejecutora - UE
artículos
Título:
Electrical Trees in Silicone Gel: A Combination of Liquid and Solid Behaviour Patterns
Autor/es:
S. J. DODD; L. M. SALVATIERRA; L. A. DISSADO; E. E. MOLA
Revista:
2013 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (CEIDP 2013)
Editorial:
IEEE. INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS
Referencias:
Año: 2013 p. 1018 - 1021
ISSN:
0084-9162
Resumen:
Electrical trees in liquids (streamers) occur on the nano-second
timescale and produce structures that dissipate on voltage removal and
sometimes even during voltage application. In AC fields the structures
are a combination of fine filaments from the positive half-cycle and
spheroidal cavities from the negative half-cycle. In contrast electrical
trees in solids are permanent filamentary structures with a fractal
geometry that grow on timescales of hours or longer at typical field
values. Here we present the results of tree formation in a silicone gel
under an AC applied electric field. These grow on timescales of minutes
and possess a fine branched filamentary structure as well as spheroidal
cavities. As in liquids, the cavities can collapse during tree growth.
In contrast the filamentary structure is permanent as in solids. However
the whole tree contracts following the removal of the applied voltage.
The observed stability of the partial self-healing tree features are
discussed in terms of the mixed liquid and solid features of the gel
structure.