| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for appropriately determining inner insulation deterioration of an insulating layer and securely re-impregnating the insulating layer with vanish. SOLUTION: When alcohol diluted by water with 75 to 90 mass% of alcoholic concentration is sprayed on a surface of the insulating layer, it is determined that inner insulation deterioration occurs in the insulating layer when conditions of (1) and (2) are satisfied. Electric apparatus winding is immersed in vanish in an impregnating tank, the impregnating tank is made into vacuum and a void is degassed. The impregnating tank is pressurized and the insulating layer is re-impregnated with vanish and the electric apparatus winding is heated and dried. The conditions are (1) Log(Rd/Rw)≥2, where Rd is resistance value of the insulating layer in a drying state, and Rw is a resistance value of the insulating layer after alcohol is sprayed, and (2) a time when the insulation resistance of the insulating layer is recovered by 50%≥60 seconds. COPYRIGHT: (C)2011,JPO&INPIT |
