PARTIAL-DISCHARGE SENSOR OF GAS-INSULATED ELECTRIC APPARATUS

摘要

PROBLEM TO BE SOLVED: To reduce the influence of external noises on the sensing of a partial discharge of a gas-insulated electric apparatus, by comparing a spectrum including a resonance frequency with an electromagnetic wave signal spectrum, and by confirming the coincidence of the frequency having a large spectrum intensity with the resonance frequency to decide the generation of the partial discharge inside the metallic containers of the electric apparatus. SOLUTION: A computer 34 compares the spectrum analyzed electromagnetic wave signal including a resonance frequency determined by the structure of a gas-insulated electric apparatus which is obtained by applying the electromagnetic wave generated in an electromagnetic wave generator 31 to the electric apparatus with the spectrum analyzed electromagnetic signal obtained from the electromagnetic wave accompanied by a partial discharge generated inside metallic containers 21, 23. Then, the computer 34 confirms the coincidence of the frequency having a large spectrum intensity with the resonance frequency to decide the generation of the partial discharge inside the metallic containers 21, 23. Thereby, the sensing accuracy and sensibility of the partial discharge can be improved with the reduced influence of external noises thereon.