| 摘要 |
<p>PURPOSE:To enable a highly sensitive measurement at a low cost and with a simple construction by utilizing an earth-side sealed ring provided near a connection of a metal container and a bushing to detect a radiation electromagnetic wave attributed to a partial discharge. CONSTITUTION:A metal bar 8 is fastened on an upper flange 2b of a metal container 1 with a bolt and an earth-side sealed ring 6 is fastened at the tip thereof. The ring 6 is divided in two and a lower sealed ring 6b is insulated with an insulating material 6c from the container 1, the bar 8 and an upper sealed rings 6a. Then, as a pulse being propagated through the container 1 reaches a boundary between the container 1 and a bushing 3, an electromagnetic wave attributed to a partial discharge is radiated intensely to outside for the first time as the container 1 is terminated and a voltage is induced by a radiation electromagnetic wave in the ring 6b to be introduced to a partial discharge measuring device 12 via an optical fiber link 10, where characteristic thereof is detected. This enables measurement with an expressly high sensitivity on the field with an inexpensive device with a simple construction.</p> |
