Inspec keywords: power transformer insulation; ageing; moisture; paper; dielectric materials; transformer oil; space charge; composite materials

Other keywords: high-voltage direct current environment; space charge accumulation; charge de-trapping properties; oil-paper insulation degradation; composite dielectric; conventional IRC model; trapped charge distribution; oil-pressboard insulation; shallow traps; moisture contents; moisture ingression; IRC measurement; dielectric properties; moisture effects; dipole relaxation process; ageing conditions; frequency domain spectroscopy measurements; de-trapping behaviour; insulation health; trap depth; isothermal relaxation current; dipolar relaxation; oil-impregnated pressboard specimens

Subjects: Organic insulation; Transformers and reactors