Electrical treeing and ageing characteristics in cavities of low density polyethylene dielectrics on partial discharge measurements

The behavioral acceleration in electrical ageing tests for low-density polyethylene (LDPE) samples embedded a gas-filled cavity is experimentally undertaken to examine the time-evolution of partial discharge (PD) events so that the degradation mechanisms on the cavity surface by internal discharges until the growth of trees can be studied. The experimental data of localized erosion by treeing growth is closely analyzed to detail the corresponding PD characteristics with microscopic techniques in terms of chemical by-products to identify the distinct phenomenon of electrical tree growth from a cavity.