Patent · US Expired

Method and apparatus for the detection of short circuits

US3970901A · kind A · utility

10Cited by
9References
22Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 6, 1974
Grant dateJul 20, 1976
Priority date
Expiry dateDec 6, 1994

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H3/087
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method for the detection of short circuits in electrical installations, in particular on railway contact wires, comprising: generating a signal corresponding to the derivative with respect to time of the monitored current, comparing the generated signal with at least one limit value, indicating a short circuit if the generated signal exceeds a limit value, monitoring the behavior of the monitored current for the occurrence of a criterion indicating the probability of a short circuit, triggering a replica signal corresponding to the behavior of the monitored current from the movement of occurrence onwards as a function of the probability criterion, comparing the replica signal with at least one limit value, and indicating a short circuit if the limit value is exceeded.

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