Ground fault monitoring device for an electrical power distribution system
US5402071A · kind A · utility
8Cited by
10References
7Claims
0Family size
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Inventors
Key dates
| Filing date | Apr 6, 1993 |
| Grant date | Mar 28, 1995 |
| Priority date | — |
| Expiry date | Apr 6, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/385
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The monitoring device comprises a measuring channel of the ground fault voltage, a measuring channel of the ground fault current, and a digital processing circuit whose role is to search for and indicate the presence of a ground fault. The processing circuit determines the fundamental parts of the ground fault current and voltage to compute the phase difference .phi. between the two parts and the cos .phi. value. The evolution of this phase difference is representative of a fault.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.