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:
Apr. 16, 1985
Filed:
Mar. 22, 1983
Paul Bulaty, Wettingen, CH;
Ivan De Mesmaeker, Windisch, CH;
Zdenek Franc, Gebenstorf, CH;
Giuseppe Salerno, Untersiggenthal, CH;
BBC Brown, Boveri & Company, Limited, Baden, CH;
Abstract
The invention relates to a method and a system for analyzing the secondary current (J.sub.2) of a current transformer (20), the primary side of which is connected into a line (10) of an electric energy supply network. When the current transformer (20) is saturated as the result of a short-circuit on the line (10), a saturation signal (X) indicating this saturation and a polarity signal (P) indicating the polarity of the displacement of the short-circuit current (J.sub.1) are generated. The two signals (X, P) are used to select zero transitions of the secondary current (J.sub.2), corresponding to the polarity of the displacement of the short-circuit current (J.sub.1). After the selected zero-transitions, the secondary current (J.sub.2) is extrapolated by a current signal (C), in accordance with its saturation-free curve-shape. The current signal (C) is finally supplied to protective systems, instead of the secondary current (J.sub.2).