Elektrischer Leiter, der mit einer elektrischen Isolierung umgeben ist

摘要

An electrical conductor is provided with an electrical insulation (11) surrounding the conductor (10) and a surrounding protective layer (12) which protects the insulation against degradation caused by corona. The protective layer consists of an organic polymer containing at least 10 per cent by volume of a powdered filler material in the form of chromium oxide, iron oxide, or a mixture of chromium oxide and iron oxide. The filler preferably has an intrinsic resistivity of 10<4> - 10<8> ohm m. The thickness of the protective layer is preferably smaller than the thickness of the underlying insulation (11) and its resistivity preferably exceeds 10<1><0> ohm m. The conductor is used, among other things, in windings and coils for electrical machines.