新しい低誘電率プレスボードを用いた超高圧大容量変圧器絶縁の開発

抄録

A pressboard providing both low permittivity and good mechanical properties is required as for insulating material in oil-immersed large power transformers insulation. Using a newly developed pressboard, insulation characteristics of inter-coil models are investigated under lightning impulse and AC voltage conditions. It is demonstrated that a spacer fabricated from the new pressboard material (permittivity of 3.5) increases the partial discharge inception and breakdown voltages up to 30%, compared with those of conventional pressboard spacers (permittivity of 4.7)