Investigation into the formation of positive charge packets in polyethylene

The phenomenon of charge packets in polymeric insulation materials under the application of dc electric fields has been reported for many years. These charge packets lead to substantial modification of local electric stress, which increases the failure possibility of the insulation. The physics of charge packets has not yet been clearly understood. In this paper, the velocity of positive charge carriers was measured. The importance of this velocity is examined through numeric simulation, which explains the formation of charge packets.