METHOD TO IMPREGNATE WINDINGS OF ELECTRICAL MACHINES Russian patent published in 2013 - IPC H02K15/12 

FIELD: electricity.

SUBSTANCE: winding and an impregnated composition are heated to impregnation temperature, and one of front parts of the winding is submerged into an impregnation composition. After the impregnation composition appears on the other front part of the winding, the winding is withdrawn from the composition and dried. During impregnation one of front parts of the winding, as well as inner and outer cylindrical parts of the winding magnetic core, are sealed from environment by means of placement into protective jackets. The second unsealed front part of the winding is submerged into a vessel with the impregnation composition, and vacuum of around 40-50 Torr is pulled with the help of a vacuum booster pump, above the upper non-submerged front part of the winding. The method development is the fact that the vessel with the impregnation composition and the front part of the winding submerged into it is sealed, and the pressure of up to 1.5-2 atm. is injected into the specified vessel. The further development of the method is the fact that after impregnation the vessel with the impregnation composition is unsealed, the lower front submerged part of the winding is withdrawn, heating current is connected to winding wires, winding temperature is increased to (40-50)°C, and the specified winding is maintained in the winding for (15-20) minutes, afterwards the vacuum booster pump is disconnected, protective jackets are unsealed, winding is withdrawn from them with a magnetic core, and dried at final temperature, for instance, 120°C for 4-5 hours.

EFFECT: improved efficiency of impregnation, reduced power inputs for preliminary drying and increased impregnation ratio.