Abstract: A winding assembly for a transformer, in particular with a medium operating voltage of Um?79.5 kV, wherein the winding assembly includes at least one winding, which ends in a winding conductor, where the winding conductor is connected to a switching line, which is configured to interconnect the winding to other windings, and where the connection of the switching line to the winding conductor is arranged inside the winding so as to reduce the danger of partial discharges and flashovers in the high-voltage end-line region for high-temperature applications.

Abstract: A winding assembly for a transformer, in particular with a medium operating voltage of Um?79.5 kV, wherein the winding assembly includes at least one winding, which ends in a winding conductor, where the winding conductor is connected to a switching line, which is configured to interconnect the winding to other windings, and where the connection of the switching line to the winding conductor is arranged inside the winding so as to reduce the danger of partial discharges and flashovers in the high-voltage end-line region for high-temperature applications.

Abstract: Method of performing condensation reactions, acylations or of preparing heterocycles comprising forming cyclic phosphonic anhydride of the formula (III) by a) reacting phosphonic acid derivatives of formula (I) with acetic anhydride at a temperature ranging between 30 and 150° C. while separating a mixture of ethanoic acid and acetic anhydride by means of distillation, b) then reactively distilling the oligomeric phosphonic acid anhydrides of formula (II) obtained in step a) and transforming the same into the corresponding cyclic trimeric phosphonic acid anhydrides of formula (III), wherein n represents a number between 0 and 300 while R represents allyl, aryl, or open-chain, cyclic, or branched C1 to C8 alkyl radicals, aryloxy, allyloxy, or alkoxy comprising open-chain, cyclic, or branched C1 to C8 alkyl radicals. Preferably the cyclic trimeric phosphonic acid anhydrides formed in step b) are immediately dissolved in an organic solvent that exhibits an inert behavior relative thereto.

Abstract: Disclosed is a method for producing cyclic phosphonic acid anhydrides of formula (III) by a) reacting phosphonic acid derivatives of formula (I) with acetic anhydride at a temperature ranging between 30 and 150° C. while separating a mixture of ethanoic acid and acetic anhydride by means of distillation, b) then reactively distilling the oligomeric phosphonic acid anhydrides of formula (II) obtained in step a) and transforming the same into the corresponding cyclic trimeric phosphonic acid anhydrides of formula (III), wherein n represents a number between 0 and 300 while R represents allyl, aryl, or open-chain, cyclic, or branched C1 to C8 alkyl radicals, aryloxy, allyloxy, or alkoxy comprising open-chain, cyclic, or branched C1 to C8 alkyl radicals. Preferably the cyclic trimeric phosphonic acid anhydrides formed in step b) are immediately dissolved in an organic solvent that exhibits an inert behavior relative thereto.