Effect of the Aging Status on Ionization of Oil Immersed Paper

Oil immersed paper is the main insulating materials used in converter transformers. The aging process of oil immersed paper is accompanied by the complete cycle of the application of oil paper insulation system, and aging will cause irreversible deterioration of the insulation performance of oil immersed paper. In this paper, epoxy is used as a barrier material to construct a triple-layer sample (i.e. epoxy/oil immersed paper/epoxy) and the PEA method is used to measure the space charge distribution in the triple-layer sample at different aging status. By comparing the charge accumulation on the interface of the triple-layer sample at different aging status, we can find that as the aging status deepens, the amount and the accumulation speed of ionized charges will increase. This shows that aging makes the oil immersed paper produce more easily ionized substances, which will cause more serious electric field distortion.