Conduction and space charges in polymeric dielectrics and nanocomposites

Polymeric dielectrics are considered important for several inherent advantages over conventional dielectric materials. Low density polyethylene and cross linked polyethylene are being popularly used as insulation for ac cable application. However, application of these polymers for dc cable insulation is hindered with space charge accumulation. New materials with nano-sized particles included in base polymers were tried out with some successes. But the space charge formation is yet to be understood. Several attempts were made earlier to understand the relation between leakage current conduction in dielectrics and space charge formation. The author presents an understanding on the relation between conduction and space charge and also puts forth recent developments. How nanocomposites could possibly block space charges is also presented.