| 摘要 |
<p>PURPOSE:To detect partial discharge pulse with high precision without being influenced by external noise by arranging a floating electrode for detecting partial discharge and commercial frequency signal, a partial discharge detecting section, a main circuit voltage phase detecting section from the commercial frequency signal, and an arithmetic section for measuring the partial discharge of an arbitrary phase. CONSTITUTION:When partial discharge is generated in the internal section of the equipment of a gas insulating switchgear, then high frequency signal is superposed on commercial frequency, and the input to a detecting section 7a is provided. Then, by band-pass filters 13, 20 in the detecting section 7a, the signal of specific frequency including partial discharge pulse, and the commercial frequency are separated from each other. The output of the specific frequency signal including the partial discharge pulse is generated as light signal in an E/O converting circuit 18, and commercial frequency signal is shaped in a pulse shaping circuit 23 and is fed to signal receiving section 7b through an optical fiber 19. By an arithmetic section 29, a measuring start time and a measuring time interval are controlled, and by the output of an A/D converting section 28, partial discharge generation is discriminated.</p> |
