Modeling the treeing growth in solid electrical insulations

This paper presents an attempt of modelling the treeing structures expanding in an insulating polymer. By assuming the treeing shapes to simple geometries and by considering the polymer/tree interface with or without charge, we establish a mathematical expression describing the dynamics of the propagation. This shows the treeing length dependency on many parameters such as the amplitude, the duration and the shape of the applied voltage, the frequency, the electrode gap, the density of the polymer, the permittivities and conductivities of both polymer and tree. We also discuss the time-lag to breakdown