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:
Dec. 20, 1994
Filed:
Dec. 30, 1992
Applicant:
Inventors:
Leif Eriksson, Sala, SE;
Murari M Saha, Vaster.ang.s, SE;
Assignee:
Asea Brown Boveri AB, Vaster.ang.s, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 63 ; 361 65 ; 361 87 ;
Abstract
A method and a device for preventing overstabilization of longitudinal differential protections in case of internal faults on power lines, which may take place when a fault situation, which is indicated as an external faults, is in reality an internal fault. The invention comprises criteria which finally provide information as to whether the longitudinal differential protection is to enter into operation. The criteria comprise level and directional determination of the currents which are measured in the terminals of the power lines, checking whether these have the same direction, and so on.