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: Method and device of utilizing, through heat exchanger or heat pump provided in addition to a normal cooling system, heat due to energy loss in a coil device, such as a transformer or a choke coil having a liquid-cooled interior, which includes throttling the normal cooling system so as to set a difference between the temperature of the interior liquid coolant, at a location under a casing cover of the coil device, and a maximum permissible temperature for a normal useful life of insulation for the coil winding so that the temperature of the inner coolant is lower when the coil device is under full load than when it is under partial load.

Abstract: Single-phase transformer, including windings being wound around an axis and cast in resin forming a cast resin body, the cast resin winding body having an outer surface and a rectangular window formed therein with sides disposed in given planes, a wound core formed of tape material extended through the window, two flanges being cast with and integral with the cast resin winding body on opposite sides thereof and parallel to the winding axis and to the window, the flanges having outer edges, mutually parallel inner surfaces substantially disposed in the plane of the narrow sides of the window and grooves formed in the inner surfaces in the vicinity of and parallel to the outer edges, an encapsulation for the wound core being anchored in the grooves, and a grounded metallization layer formed on the outer surface of the cast resin winding body at least immediately adjacent to the wound core.

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.