Patent · US Expired

Protective relaying system

US4561120A · kind A · utility

14Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 1, 1984
Grant dateDec 24, 1985
Priority date
Expiry dateMar 1, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H1/0069
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A protective relaying system in which the electric stations at both ends of a district of a power system to be protected optically transmit and receive reciprocally the information of the electric stations. A first protective relay device responds to both the electrical quantities from the opposite side terminal and electrical quantities of its own side terminal, and a second protective relay device responds only to the electrical quantities of its own side terminal. The respective protective relay devices are controlled by virtue of error detection circuits and signal discontinuity detection circuits connected to the optical transmission line to thereby discriminating the mere failure in the optical transmission line from the concurrent failures in both the optical transmission line and the transmission line so as to rapidly eliminate the failures.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.