Results of Partial Discharge Measurements in the Long-distance 275kV GIL

Abstract

In this paper we introduce the newly developed measuring system of partial discharges (PD) in after-laying tests on site for a long distance gas insulated transmission line (GIL) in a tunnel. We evaluated the length of harmful particles for the overvoltages to be considered for the Shinmeika-Tokai line. The detectable length of the particles by the PD sensors was compared with the harmful particles and the high sensitive PD measuring system which can locate PD signals was developed, considering noise levels in the tunnel. We applied the system to the after-laying test on site and confirmed that the developed system was effective to verify the required performance for a long distance GIL in a tunnel.