Detection of high resistance faults in electrical power supply network
US4800509A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 18, 1986 |
| Grant date | Jan 24, 1989 |
| Priority date | — |
| Expiry date | Dec 18, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/11
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
High resistance ground faults on a transmission line of an electrical power transmission network are detected with the aid of a device comprising a travelling wave model of the line located in measuring stations (P, Q) at either end of the line, which permits the voltage distribution along the line, seen both from P and from Q, to be obtained. A voltage .DELTA.U.sub.Qp is formed as the difference between a votlage in station P, calculated in the travelling wave model in Q, and the corresponding voltage one period earlier. A voltage .DELTA.U.sub.Pp is formed as the difference between a voltage calculated in the travelling wave model at P and the corresponding voltage one period earlier. The corresponding voltage differences .DELTA.U.sub.Pq and .DELTA.U.sub.Qq are calculated for station Q. The voltage difference .DELTA.P is then formed as the difference between .DELTA.U.sub.Qp and .DELTA.U.sub.Pp, and the corresponding .DELTA.Q is formed as the difference between .DELTA.U.sub.Pq and .DELTA.U.sub.Qq. Fault detection is obtained when .DELTA.P>.epsilon..sub.p or when .DELTA.Q>.epsilon..sub.q, where .crclbar..sub.p is the accepted voltage difference at P and .epsilon..sub.q is the corres…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.