Jv. Champion et al., THE CORRELATION BETWEEN THE PARTIAL DISCHARGE BEHAVIOR AND THE SPATIAL AND TEMPORAL DEVELOPMENT OF ELECTRICAL TREES GROWN IN AN EPOXY-RESIN, Journal of physics. D, Applied physics, 29(10), 1996, pp. 2689-2695
Combined partial discharge detection and video monitoring of the tree
growth have shown a strong correlation between the partial discharge a
ctivity and the spatial and temporal development of electrical tree gr
owth in CY1311 epoxy resin. CCD imaging of the spatial distribution of
light emitted, due to partial discharges in the tree structure, has s
hown that the different modes of partial discharge behaviour reflect t
heir different spatial distribution within the existing tree structure
, with new growth occurring at those parts of the tree in which the pa
rtial discharges are active. The dynamics of the partial discharge beh
aviour, namely the frequency and duration of two modes of activity, is
controlled by the experimental conditions (voltage and pin-plane spac
ing) and determines the type (fractal dimension) of the resultant tree
. During one mode of activity, rapid low-fractal-dimension radial grow
th of the tree occurs. During the other mode, new growth occurs at a s
lower rate from the tree structure near the pin electrode, leading to
an increase in the overall fractal dimension of the tree structure.