METHOD OF MAKING FRAME INSULATION OF COILS OF HIGH VOLTAGE ELECTRICAL MACHINES Russian patent published in 2008 - IPC H02K15/12 

FIELD: electrical engineering.

SUBSTANCE: invention pertains to electrical engineering and can be used in high voltage electrical machine building. The essence of the invention lies in that, after winding on to the current conducting part, coils of porous mica containing bands, containing a hardener of a dip mix, the coil is put into a groove of a magnetic core made from electrical steel. The coil is put into a sealed treatment chamber and vacuum drying is carried out. The coil is then treated in a treatment chamber by a thermoreactive composition based on epoxy resin initially in a vacuum, and then under excess pressure. Treatment is done with heating of the coil by passing electrical current through the current conducting part of the coil. Excess compound is poured from the treatment chamber. A vacuum is formed in the treatment chamber and a water solution of the harder is injected in. Under vacuum conditions, the hardener turns into gas-vapour state. The chamber is then exposed to the atmosphere and the hardener condenses on the surfaces of the coil and inside the treatment chamber. The next thermal hardening of the frame insulation is carried out and current is also passed through the current conducting part of the coil until polymerisation temperature of the compound is attained. In the thermal hardening process, the layer of mica containing band, containing a hardener compound, polymerises at the same time as the films of compounds on the surfaces of coils and structural members.

EFFECT: higher quality of the frame insulation of coils of high voltage machines, shortening of the technological process and reduction of energy losses.