METHOD OF TRACTION TRANSFORMERS CONNECTION IN ALTERNATING-CURRENT SYSTEM OF 25 KV Russian patent published in 2015 - IPC B60M3/02 H02J3/00 

FIELD: electricity.

SUBSTANCE: method of traction transformers connection in alternating-current system of 25 kV is referred to the sphere of electric railroads and may be used to supply both traction and non-traction loads. The method of traction transformers connection in alternating-current system of 25 kV lies in at least double change in the connection procedure for windings inputs of traction transformer at each traction substation depending on wear if the traction transformer winding insulation within the whole period of its service life. For the first time switching of the traction transformer windings is made when insulation wear is reached by the most worn windings within the range of 0.30-0.40; for the second time when insulation wear is reached by the most worn windings within the range of 0.55-0.70. At that traction winding with the severest wear is connected to a neutral link of the overhead system while traction winding with the least wear is connected to the power supply branch of traction substation.

EFFECT: increased service life of the traction transformer.

2 dwg, 3 tbl