The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 05, 2000
Filed:
Nov. 17, 1997
Tetsu Shiota, Osaka, JP;
Hideki Tokura, Osaka, JP;
Kenji Morimoto, Osaka, JP;
Takaho Tanaka, Osaka, JP;
Yoshiharu Kaneda, Hyogo, JP;
Keiichi Itoh, Hyogo, JP;
Ken Kimura, Hyogo, JP;
Shigeo Kitamura, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Kansai Electric Power Co., Inc., Osaka, JP;
Abstract
A defect detecting apparatus for monitoring an electrical equipment for defects, the electrical equipment having a resonance frequency. The defect detecting apparatus includes a sensor operatively connected to the electrical equipment for sensing a signal indicating a defect in the electrical equipment; a first bandpass filter operatively connected to the sensor, the first bandpass filter having a first bandwidth and first center frequency at substantially the resonance frequency of the electrical equipment; a second bandpass filter operatively connected to the sensor, the second bandpass filter having a second bandwidth and a second center frequency higher than the resonance frequency of the electrical equipment; a signal strength comparing circuit operatively connected to the first bandpass filter and the second bandpass filter for comparing relative strengths of signals output by the first bandpass filter and the second bandpass filter; and a partial discharge measuring circuit operatively connected to the signal strength comparing circuit for measuring an output signal of the first bandpass filter relative to an output signal of the second bandpass filter to indicate a defect in the electrical equipment.