Arcing fault detection system using fluctuations in current peaks and waveforms
US5839092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1997 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | Mar 26, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H1/0015
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system for detecting arcing faults in a line conductor carrying an electrical current between a power source and a load, the electrical current defining an AC waveform comprising a series of alternating positive half cycles and negative half cycles. In one embodiment, the method comprises the steps of obtaining current samples in a series of half cycles of the waveform, determining the peak current of each of the half cycles, and comparing the peak currents to determine changes in slope between half cycles. The number of changes in slope occurring within a selected time interval are counted and an arc indicative signal is produced when the number of reversals in polarity in slope occurring within the selected time interval equals or exceeds a predetermined threshold number. In another embodiment, the method comprises, in addition to the steps above, the steps of normalizing each of the current samples and autocorrelating the normalized current samples to obtain a measure of significant waveform shape changes between consecutive half cycles. Both the number of changes in slope and the number of significant waveform shape changes occurring within a selected time interval are counte…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.