抄録
The fundamental and 3rd harmonic waves of loss current through a non-penetrated water treed polyethylene have been numerically calculated based on a model where current density j through channels interconnecting micro-voids is assumed to depend on electric field E as j =(σ0/h)•sinh(h•E), where h is a parameter which characterizes the electric field dependence of j. The numerical results obtained by this model give a good agreement with the observed changes in the magnitudes of fundamental and 3rd harmonic waves, I1 and I3, and their phase angles θ1 and θ3, respectively, for the application of a constant voltage. It has been concluded that the length of interconnected channels in the water treed region grows with time duration. It is also concluded that conductivity of interconnected channels shows a little increase with their growth.
