DEVELOPMENT OF FLASHOVER VOLTAGE TEST METHOD FOR SNOW ACCRETED INSULATORS-PRELIMINARY TEST WITH 33 KV CLASS INSULATOR SAMPLES -

摘要

As the preliminary attempt to develop a 154 kV class full-scale snow test procedure to be used for evaluation of various insulator designs, flashover voltage tests of snow accreted insulators were carried out with 33 kV class insulator samples. The test procedure consisted of four steps, 1) generation of artificial snow with defined conductivity, 2) accretion of packed snow on the insulator, 3) increase of liquid water content of the accreted snow, 4) voltage application. The voltage tests showed that the level of flashover voltage was comparable with the service voltage during the Niigata field outage, and the results were also repeatable. The test method was preliminary verified for the full-scale transmission class insulators.