Fault current detecting circuit
US9093838B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 10, 2013 |
| Grant date | Jul 28, 2015 |
| Priority date | — |
| Expiry date | Mar 19, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H9/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The fault current detecting circuit includes: a current detection unit that outputs a current detection signal; a first comparing circuit unit that compares the current detection signal with a predetermined reference current value and outputs a first output signal; a differentiator that differentiates the current detection signal to output a change slope of the current detection signal; a second comparing circuit unit that compares the change slope with a predetermined reference change slope value and outputs a second output signal; a third comparing circuit unit that compares the current detection signal with a predetermined current detection limit reference value and output a third output signal; and a trip determining unit that outputs a trip control signal only when the first output signal and the second output signal are maintained to be received and the third output signal is not received.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.