Topological mapping of disruptive discharges in extruded dielectrics–part I mapping of the discharge path

A close observation and analysis of the failure path in the breakdown of electrical cables is presented as implementation of the statistical framework of Weibull statistics. Previous works [1] and [2] have shown Weibull distribution as suitable statistics for the analysis of the electrical endurance of cables, even though only information regarding the bulk can be gotten. To overcome this problem, a topological map of the failure path made evident some correlation between this path and ultimate polymer rheology, using three cylindrical variables (r, θ) as further data. These variables are (r
1
, θ
1
) failure region, (r
2
, θ
2
) minimum thickness region, and (r
3
, θ
3
), maximum thickness region. This statistical implementation allows the technologists to deal with cable extrusion process in a consistent way.