Detection of subsidence current in the determination of circuit breaker status in a power system
US5914663A · kind A · utility
10Cited by
4References
36Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 16, 1997 |
| Grant date | Jun 22, 1999 |
| Priority date | — |
| Expiry date | Oct 16, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/3272
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The apparatus detects subsidence current from unfiltered as well as filtered secondary current values in the current transformer. A lack of zero crossings during a predetermined period is a reliable indication of the presence of subsidence current. If subsidence current is detected, then a signal is generated which indicates that the circuit breaker for the power system has opened, providing an accelerated indication thereof relative to an indication produced by an overcurrent element dropping out.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.