Patent · US Expired

Zero sequence current source for transformer having a nonwound tertiary

US4231074A · kind A · utility

5Cited by
6References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 18, 1978
Grant dateOct 28, 1980
Priority date
Expiry dateSep 18, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H3/162
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A three-phase electrical transformer utilizes a conductor independent of the transformer windings for sensing zero sequence current upon the occurrence of a ground fault. A current transformer coupled with the independent conductor provides polarization to protective relay devices. One embodiment utilizes the transformer internal tank shield in combination with the current transformer for providing zero sequence current.

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