A wrapping tape insulation system is provided which includes an insulating tape preferably produced by vacuum pressure impregnation. The provided tape comprises a tape adhesive, a tape accelerator and a resin wherein the tape accelerator may comprise an imidazole covalently bonded via the amino function to an acrylate by aza-Michael addition.

Disclosed is an anhydride-free insulation system for insulating an electrical conductor or a coil of conductors, comprising: (a) a liquid epoxy resin formulation comprising at least 80% by weight, based on the liquid epoxy resin bath formulation, of bisphenol A diglycidyl ether, (b) a mica tape comprising a mica paper adhered by means of a binder to a support (c) an imidazole compound of the formula (I)

##STR00001##

wherein R.sup.1, R.sup.2 and R.sup.3 are individually selected from hydrogen, branched or unbranched C.sub.1-C.sub.4-alkyl, phenyl and benzyl, provided that at least one of R.sup.1 and R.sup.2 is hydrogen.

Disclosed is an anhydride-free insulation system for insulating an electrical conductor or a coil of conductors, comprising: (a) a liquid epoxy resin formulation comprising at least 80% by weight, based on the liquid epoxy resin bath formulation, of bisphenol A diglycidyl ether, (b) a mica tape comprising a mica paper adhered by means of a binder to a support (c) an imidazole compound of the formula (I)

##STR00001##

wherein R.sup.1, R.sup.2 and R.sup.3 are individually selected from hydrogen, branched or unbranched C.sub.1-C.sub.4-alkyl, phenyl and benzyl, provided that at least one of R.sup.1 and R.sup.2 is hydrogen.

Tape adhesives suitable for impregnating processes for insulation systems are described. Embodiments of the tape adhesives include solid insulation material such as mica, anhydride-free impregnating resins and accelerators for the anhydride-free impregnating resins. The tape adhesives may be adjusted with respect to the reactivity of the accelerators for the anhydride-free impregnating resins in relation for the storage stability of the overall insulation systems.

Tape adhesives suitable for impregnating processes for insulation systems are described. Embodiments of the tape adhesives include solid insulation material such as mica, anhydride-free impregnating resins and accelerators for the anhydride-free impregnating resins. The tape adhesives may be adjusted with respect to the reactivity of the accelerators for the anhydride-free impregnating resins in relation for the storage stability of the overall insulation systems.

The present disclosure relates to insulation systems. The teachings thereof may be embodied in an insulation system for an electrical machine. For example, an insulation system may comprise: solid insulation materials; an impregnating resin having oxirane functionalities; a depot accelerator distributed throughout the solid insulation materials; and a catalyst for initiating hardening of the impregnating resin, wherein the catalyst is at least partly in gaseous form under hardening conditions.

The present disclosure relates to insulation systems. The teachings thereof may be embodied in an insulation system for an electrical machine. For example, an insulation system may comprise: solid insulation materials; an impregnating resin having oxirane functionalities; a depot accelerator distributed throughout the solid insulation materials; and a catalyst for initiating hardening of the impregnating resin, wherein the catalyst is at least partly in gaseous form under hardening conditions.

An insulative assembly includes an insulative mica-based carrier film and first and second resistive grading layers joined to opposite sides of the mica-based carrier film. The first resistive material layer is configured to engage one or more conductors and insulate the one or more conductors from at least one other conductor. A method for creating an insulative assembly for one or more conductors includes obtaining an insulative mica-based carrier film, depositing a first resistive grading layer on a first side of the mica-based carrier film, and depositing a second resistive grading layer on an opposite, second first side of the mica-based carrier film.

An insulative assembly includes an insulative mica-based carrier film and first and second resistive grading layers joined to opposite sides of the mica-based carrier film. The first resistive material layer is configured to engage one or more conductors and insulate the one or more conductors from at least one other conductor. A method for creating an insulative assembly for one or more conductors includes obtaining an insulative mica-based carrier film, depositing a first resistive grading layer on a first side of the mica-based carrier film, and depositing a second resistive grading layer on an opposite, second first side of the mica-based carrier film.

An assembly and a method for manufacturing an insulation layer of an electrical conductor are presented. The electrical conductor is enclosed in a cavity of a mold. Spacers embedded into holes of the mold are movable into the cavity for holding the electrical conductor in the cavity to maintain a gap between the electrical conductor and surface of the cavity. Distance of the gap is defined by thickness of the insulation layer. Spacers are movable into the holes of the mold from the cavity to maintain even surface of the cavity. Insulation compound fills entire gap and is cured to form the insulation layer having homogenous thickness.