STUDY ON AN AFTER-LAYING TEST FOR A LONG-DISTANCE GIL

Technologies for the after-laying test of a long-distance gas insulate d transmission line (GIL) have been developed for the detection oi par tial discharge (PD) and contact defects. We constructed long (168 m) t est line in a deep tunnel and clarified the propagation characteristic s of PD signals through the GIL as well as the spatial sensitivity and S/N characteristics of PD sensors for locating metallic particles, We have also proposed the application of a fiber-optic temperature distr ibution sensor for locating contact defects and confirmed the validity of this sensor for the GIL test line.