抄録
In recent years, with the high faculty and the large capacity of electrical machines, the size of insulating materials used in those machines has become larger and larger, and the high arc resistance has been demanded on the electrical machines with arcing, especially. Since various spatial configurations of these constitution materials are being used, the effect of spatial configurations of samples on arc resistance of electrical insulating materials is a quite important factor for insulation design.
In this paper, the arc resistance tests of large size sample were carried out under the different conditions from the previous arc resistance test, and the effect of spatial configurations of samples was studied. As the test procedure, the max. applied voltage was 50kV, the arc current was 10mA and the electrode gap length was 6∼50mm. Other test conditions were the same as those of the ASTM method. As the test samples, various plastics were used. The variations of arc resistances were tested by changing the angle of inclination.
As the result, the effect of spatial configurations of samples on arc resistance was noticed when the gap length was comparatively large, and the arc resistance decreased when the samples were at the inclined configuration from the horizontal one. The arc resistance decreased only 61∼65% of the value at the horizontal configuration at a certain electrode gap length. In conclusion, the arc resistance is affected significantly by the spatial configurations of samples as well as their size, such as gap length.
