SIMULATION OF TREE PROPAGATION IN POLYETHYLENE IN PLANE-PLANE ELECTRODE ARRANGEMENT USING CELLULAR AUTOMATA: THE EFFECT OF HOMOCHARGES AND HETEROCHARGES

摘要

The electrical tree propagation is simulated in the present paper with the aid of Cellular Automata. The plane-plane electrode arrangement is used and the sample is considered to be polyethylene with a variation of dielectric constant between the values of 2.2-2.4. A DC voltage of +250 kV is applied to the upper electrode creating a nearly uniform electrical field. The electrical tree emanates from a discontinuity of the plane electrode and propagates inside polyethylene sample. The case of a uniformly distributed positive and negative space charges is studied which leads to field distortion. Both the presence and the polarity of space charges affect the electrical tree formation and determines the propagation or not of the dendrite.