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:
Jul. 23, 2002
Filed:
Aug. 11, 1999
Toshiaki Rokunohe, Hitachi, JP;
Fumihiro Endo, Hitachi, JP;
Tokio Yamagiwa, Hitachi, JP;
Ryouichi Shinohara, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An insulated device diagnosing system is capable of judging the deterioration, lifetime, and defects of a device. The intensity at each voltage phase angle is measured at a plurality of specific frequencies, taking high voltage phase angles as the abscissas. The deterioration, lifetime, and the kind and extent of abnormality of the device are judged from the pattern and intensity of the spectral distribution, which is obtained by peak-holding the measured intensity for a defined time period. According to the present invention, partial discharge can be measured highly sensitively and precisely to diagnose the deterioration, lifetime and the extent of defect of the device. As a result, the insulation reliability of the device can be improved, and the part of the device that should be repaired/replaced can be grasped before disassembly of the device, thereby cutting the maintenance cost.