Space charge accumulation after ac ageing and its effect on dc poling has been studied in lowdensity polyethylene (LDPE). LDPE film samples with thickness of around 180µm were aged at an electric stress of 50kV/mm under 50 Hz ac voltage for various times at ambient temperature. Space charge dynamics in the samples after ageing were monitored using the pulsed electroacoustic (PEA) technique. Except the presence of considerable amount of space charge accumulation in the aged sample, the ageing has also brought a significant influence into the space dynamic under dc poling voltage. The ageing extent was previously investigated by chemical analysis (i.e. Fourier Transform Infrared FTIR and Raman spectrum) revealed little change taken place in the bulk of the material after ac ageing in the time frame studied. This indicates that the space charge measurement may be an effective method for diagnosing the early stage of material deterioration. It also provides additional information about charge mobility and trap depth that can be extracted from space charge profile.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.