Research on the Impulse Breakdown Mechanism of the Dielectric as Used in Oil-Filled Cables

The impulse breakdown of oil-impregnated paper alone, paper in combination with polyethylene, and polyethylene alone were investigated. Tape thickness and oil-gap or butt-space size were the sample variables, with the total insulation thickness remaining constant. Results substantiated that the impulse breakdown of paper varied inversely with the tape thickness. The impulse breakdown of polyethylene was independent of tape thickness. The presence of oil in the butt spaces of both materials was of no consequence.