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:
May. 16, 2000
Filed:
Aug. 15, 1994
Fumihiro Endo, Hitachi, JP;
Tomoaki Utsumi, Hitachi, JP;
Toshio Ishikawa, Hitachi, JP;
Shuzo Iwaasa, Hitachi, JP;
Tokio Yamagiwa, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a gas insulated electric apparatus having gas sections filled with insulating gas, a locating device determines a position of a gas section in which an insulation abnormality is detected, on the basis of a detection signal from sensors disposed in each of predetermined gas sections. At the same time a hindering degree diagnosing device diagnoses the degree and the kind of the insulation abnormality, by comparing a detection signal from the sensors with data stored in a data base. A valve control generates a valve control signal, responding to the locating device and the hindering degree diagnosing device, and in response to the valve control signal, a trip circuit generates a valve opening signal to open an electromagnetic valve disposed in a gas section in which an insulation abnormality is detected. An insulating gas injecting and evacuating device injects an insulating gas, different from the initial insulating gas with which the gas sections are filled beforehand, into the gas section for which the electromagnetic valve has been opened by the valve opening signal, or evacuates a predetermined amount of the insulating gas with which the gas sections are filled beforehand, so as to increase insulation strength.