Abstract: Method of manufacturing a transformer winding embedded in casting resin by winding coils respectively by themselves and independently of one another for disposition thereof in tandem in axial direction of the winding includes placing the wound coils in a substantially annular casting mold having an inner and an outer jacket, with respective impregnated corrugated mats of insulating material as spacers disposed between the inner jacket and the coils as well as between the coils and the outer jacket, the inner and the outer jackets being fixed between mold end walls at respective ends of the casting mold; and disposing the casting mold containing the wound coils in an evacuated chamber and pouring casting resin into the casting mold through an axially parallel slot formed in the outer jacket thereof.

Abstract: A dry-type transformer cast into casting resin, includes windings, a main leakage canal, at least one of the windings being subdivided into coaxial winding parts spaced apart from each other defining an additional axial cooling canal therebetween, separate inner and outer casting resin bodies each having end faces and being cast around a respective one of the winding parts, reinforcements formed on diametrically opposite outer surface regions of the outer casting resin body for receiving axially extended connecting conductors for electrically wiring the winding parts, line terminals and tap terminals disposed on respective reinforcements, and elastic blocks common to all of the windings and winding parts between which the winding parts of a respective winding are clamped and metallically interconnected in front of the end faces of the casting resin bodies.

Abstract: Multiphase transformer for power distribution in a supply network includes a single block of cast resin having high voltage and low voltage conductor windings embedded therein, and an iron core with a plurality of legs and an upper and lower yoke formed of closely-stacked transformer laminations centrally embedded in the block, the block having axially-extending ribs integral therewith defining troughs between the ribs and defining spaces between the ribs and the core, legs and yokes, watertight caps disposed between the ribs closing off the troughs and holding the core, legs and yokes, and mechanically compacted dry quartz sand filled in the space.