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:
Jun. 01, 1982
Filed:
Dec. 21, 1979
Applicant:
Inventor:
Tetsuo Matsushima, Fuchu, JP;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
364492 ; 364483 ; 361 80 ;
Abstract
In a method and a system for protecting an electric power system, a signal useful for the protection is produced through operation on a digital data q.sub.m indicative of an instantaneous value at a first time point of an AC electrical quantity and another digital data given by 1/2{axq.sub.m-n -(2-a)xq.sub.m-n+l } where q.sub.m-n and q.sub.m-n+l represent data indicative of instantaneous values of an AC electrical quantity, at a time point in advance of the first time point by an angle of .alpha..degree. (0.ltoreq..alpha..ltoreq.180), and at a time point lagging behind the first time point by an angle of (180-.alpha.).degree., respectively, and a equals to .alpha./90.