Abstract:
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.
