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:
Oct. 09, 2007
Filed:
Feb. 21, 2006
Applicant:
Branislav Cvorovic, Stafford, GB;
Inventor:
Branislav Cvorovic, Stafford, GB;
Assignee:
Areva T&D UK Limited, Stafford St, GB;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 31/08 (2006.01); G01R 31/06 (2006.01); H02H 3/26 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method of supervising the operation of a plurality of current transformers arranged in respective groups and connected to a protection relay forming part of a three-phase electrical power system includes determining a current ratio at an output of each group of current transformers, comparing each current ratio with a predetermined high ratio, comparing each current ratio with a predetermined low ratio, and generating a fault indication when the current ratio at one location exceeds the predetermined high ratio and the current ratio at the or each other location remains below the predetermined low ratio.