Dynamic energy threshold calculation for high impedance fault detection
US7085659B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 2004 |
| Grant date | Aug 1, 2006 |
| Priority date | — |
| Expiry date | Oct 15, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A technique for dynamically determining the occurrence of a high impedance fault (HIF) independent of load. An HIF algorithm provides the energy value for a given number of samples of the input signal that is phase (load) currents and/or neutral (residual) current. The input signal energy value is multiplied by a factor that ranges from about 110% to about 300% to calculate a threshold energy value and the result of that calculation is stored in a buffer. A HIF detection signal is generated when the energy value determined for samples of the input signal that are the same in number as the given number of samples and taken after the given number of samples is greater than an energy value derived from a predetermined number of the calculated threshold energy values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.