Study on the Electrical Tree Propagation Evolution in Polymer Composites via Phase Field Method

Polymer composites have been broadly used in electrical and electronic applications, in which fillers are incorporated into polymers to achieve better properties. As electrical trees are a typical cause of insulation failure in dielectric polymers, the addition of fillers in polymer composites has also raised new problems concerning electrical treeing. The phase field method was utilized in this work to simulate the propagation of electrical trees in polymer composites. The permittivity of fillers was proved to influence the trajectory of treeing, which should be attributed to the distorted electric field around the fillers. The propagation rate in terms of tree length and damaged volume with respect to time was calculated, which was affected by the critical energy densities of the fillers and polymers.