66/77kV系統の送電線を対象とした2並列気中ギャップの同時フラッシオーバ特性

抄録

We investigate concurrent flashover characteristics under short-tail lightning impulse voltage by using two parallel gaps in air assuming multi-phase back-flashover for 66/77kV overhead transmission lines. The experiment is conducted by using two types of experimental cases. One is rod-rod/rod-rod electrode parallel configuration, the other is EGLA/rod-rod. Short-tail lightning impulse voltage is applied by using a 12MV impulse generator in Shiobara Testing Yard of CRIEPI assuming that lightning strikes a transmission tower. DC voltage is superimposed on one side of two parallel gaps in consideration of the effect of AC phase difference in the actual transmission lines. As a result, we experimentally clarify that concurrent flashover occurs at the flashover electric field E_FO from 0.83 to 1.22kV/mm in the air gap.