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. 01, 2006
Filed:
Oct. 15, 2004
John Peterson, Jeffersonville, PA (US);
Ratan Das, Laflin, PA (US);
Mohamed Y. Haj-maharsi, Raleigh, NC (US);
John Peterson, Jeffersonville, PA (US);
Ratan Das, Laflin, PA (US);
Mohamed Y. Haj-Maharsi, Raleigh, NC (US);
ABB Technology AG, Zurich, CH;
Abstract
A technique for dynamically determining the occurrence of a high impedance fault (HIF) independent of load. An HIF algorithm provides the energy value for a given number of samples of the input signal that is phase (load) currents and/or neutral (residual) current. The input signal energy value is multiplied by a factor that ranges from about 110% to about 300% to calculate a threshold energy value and the result of that calculation is stored in a buffer. A HIF detection signal is generated when the energy value determined for samples of the input signal that are the same in number as the given number of samples and taken after the given number of samples is greater than an energy value derived from a predetermined number of the calculated threshold energy values.