Alternating current power loss detector
US4855722A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1986 |
| Grant date | Aug 8, 1989 |
| Priority date | — |
| Expiry date | Aug 1, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/24
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The duration of time during which an AC power voltage sinusoidal waveform remains between negative voltage threshold -V1 volts, nominally 5% of negative peak voltage -V2 volts, and positive voltage threshold +V1 volts, nominally 5% of peak positive voltage +V2 volts, is detected. By the change in voltage with time exhibited by a sinusoidal waveform in the region of zero voltage crossing, the expected time duration between voltage thresholds in approximately 5% of one-half period of such sinusoidal waveform. If the actual time between voltage thresholds exceeds (nominally) twice this value, or 10% of one-half period, then a power black-out condition is sensed, and a power fault signal is produced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.