Method and apparatus for the distance-selective fault monitoring of electrical lines
US4222085A · kind A · utility
3Cited by
4References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 25, 1978 |
| Grant date | Sep 9, 1980 |
| Priority date | — |
| Expiry date | Aug 25, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/382
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of, and apparatus for, the distance-selective monitoring of faults at electrical lines by means of a quadrilateral trigger or trip region. There are formed at least two reference signals of at least approximately the same phase and from each of these reference signals and the line voltage there is formed a respective difference signal. Each difference signal experiences a separate comparison with a related threshold phase angle in order to determine whether the monitored fault lies within or without the trip region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.