Patent · US Expired

Method and device for protecting busbars

US5619392A · kind A · utility

25Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 24, 1995
Grant dateApr 8, 1997
Priority date
Expiry dateApr 24, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H7/261
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a busbar protection method and a corresponding device, the maximum values of the currents in the outgoers are determined. The maximum values Ikmax of the current characteristics are extended by a certain hold time th. Subsequently, these current characteristics are processed further vectorially. With the aid of these current characteristics Ik changed in such a way, a fault signal is calculated by means of a protection algorithm, preferably the current comparison method with current stabilization or the phase comparison algorithm. It can be uniquely determined on the basis of the extension of the maximum according to the invention whether an external fault or an internal one is concerned. The advantage of the method and of the device according to the invention resides, in particular, in that the localization of the fault is possible in a reliable fashion even in the case of strong saturation of the current transformers. Above all, false tripping can be reliably avoided even in the case of external faults.

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