Abstract
The authors carried out an outdoor exposure test and the 5000h multiple stress test to ethylene vinyl acetate (EVA) polymer composite insulator used for 22kV distribution line and an attempt was made to estimate the acceleration factor of the 5000h multiple stress test corresponding to the climate condition of the Kyushu area. By comparing dryband arc cumulative charge of leakage current at 5000h multiple stress test with that in the outdoor exposure test, the authors estimated the acceleration factor of the 5000h multiple stress test to be about 20 times. The acceleration factor was found to almost agree with the evaluation result of the absorption of hydroxyl group by FT-IR analysis and the surface roughness of the insulator, respectively. Finally, for the electrical property, the expected life of EVA insulator that the authors developed was confirmed to be more than 40 years.
