Electric transmission line ground fault prevention systems using dual parameter monitoring with high sensitivity relay devices in parallel with low sensitivity relay devices
US11942776B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 2022 |
| Grant date | Mar 26, 2024 |
| Priority date | — |
| Expiry date | Aug 23, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H5/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including a plurality of existing low sensitivity (LS) relays and a corresponding set of high sensitivity (HS) relays in parallel with the is relays. The HS relays on each line are programmed to include: preset acceptable operating parameter ranges of at least two electric operating conditions, at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence overcurrent (and combinations thereof); monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaker on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.