A new synthetic impregnant for high tension hollow core cables

The “paper/thin mineral oil” composite dielectric used as insulation in high voltage cables dates back to 1924 when the first hollow core cable (a 130 kv pioneer) was experimentally laid at Brugherio (Milan, Italy). Since then, thanks to continuous investigations and growing experience, each single characteristic of this impregnant has been brought more and more into focus, eventually reaching the at present strictly defined features.