GB145675A - Improvements in and relating to high-tension electric transformers - Google Patents

Abstract

145,675. Siemens & Halske Akt.-Ges. June 30, 1919, [Convention date]. Transformers.-In a highvoltage transformer, the highvoltage winding is wound in layers separated by insulating- material, the axial lengths of the layers being graduated towards the outside of the winding in such a manner that the voltage drop along the periphery of the winding is nearly constant. The low-voltage winding 2 is wound on the core and is separated from the high-voltage winding by a tube 3. The end 4 of the high-voltage winding is brought to a low potential by earthing or by connecting it to the low-voltage winding. The first layer 4, 5 of the high-voltage winding is separated from the second layer 7, 8 by a layer of insulation, such as paper, and the second layer stops at a distance 9 from the beginning of the first layer. The third layer 10, 11 similarly stops at a distance from the beginning of the second layer, and so on. The thickness of the insulating- layers decreases from the inside to the outside in order to make the dielectric strain approximately the same in all the layers. The outer insulating layers are made a little thicker in order to protect the winding against wandering waves. Two highvoltage windings may be provided on the same leg of the core 1.