TRANSFORMER MANUFACTURING METHOD Russian patent published in 2016 - IPC H01F41/02 

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering, to manufacturing of transformers. During manufacturing steel strips are made for assembly of the core and stacked over each other in a pack. Windings are wound with outputs for primary and secondary windings. The windings are mounted at the core pack made of strips. The strips are bended enveloping the mounted windings with their stacking onto each other. Ends of each strip are connected and fixed thus completing assembly of the core and manufacturing of the transformer. At core assembly the pack is stacked with distribution of plates into two units containing M subpacks with M≥2. Each subpack is made of N strips with N≥1 of similar width. Width of strips in various subpacks for the same unit is different. Strips of the biggest width are placed into the pack middle during formation of the pack and subpack. The strips are placed onto each other thus forming the pack and subpack with their width reduced in direction from the pack middle to its edge. Units are formed of strips with cross-section symmetrical in regard to the axis passing through the pack centre and parallel to strip surface. In result the core pack with stepped cross-section is received, close in its shape to ellipse or sphere. Length of each strip in the pack and their placement in regard to each other in longitudinal direction is selected so that windings in the core envelope the core densely. Toe-to-toe connection of strips is considered with localization in regard to connection of ends of the adjacent strips in different places. Winding of primary and secondary windings and their mounting in the core pack is made simultaneously. The wire is wound with tension and effect of hoop stress in regard to the core pack.

EFFECT: reduced stray inductance, resistance, improved heat removal from inner rows of winding, reduced noise level.

19 cl, 4 dwg