| 摘要 |
Electromagnetic waves induced by a partial discharge which occurs at the time of internal abnormality of a gas insulated apparatus are detected by a compact antenna having a high detection sensitivity for a board frequency band. With a circular signal receiving antenna unit 4 constituted by combining two piece of semicircular conductive plates on a plane in a metallic vessel 4 for the gas insulated apparatus, the electromagnetic waves due to the partial discharge can be detected with a high sensitivity for a board frequency band. The detected signals are measured by a measuring unit 10 via a hermetical seal coaxial terminal 7 and a coaxial cable 8. Further, the antenna portions of the semicircular plates are designed to extend a large area, a capacitance with a potential measurement portion can be increased, thereby a potential measurement with a high sensitivity can also be performed. <IMAGE> |
