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:
Aug. 20, 1985
Filed:
Aug. 29, 1983
Hung J Li, Coral Springs, FL (US);
Leonid Husak, Coral Springs, FL (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
An apparatus and method for detecting a single-phase-to-ground fault on a three-phase electrical power system and for identifying the faulted phase conductor. Each phase conductor is monitored by evaluating three phasor signals associated therewith, i.e., the zero sequence current of the electrical power system, the negative sequence voltage on the phase conductor rotated 90 electrical degrees counterclockwise (or the negative sequence current on the phase conductor), and the quadrature phase voltage for the phase conductor rotated 30 electrical degrees counterclockwise. The coincidence of these three signals for a predetermined time indicates the occurrence of a single-phase-to-ground fault on the monitored phase conductor.