Fault location method and device
US6924647B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2001 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | Dec 14, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY04S10/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to a method for calculating the distance to fault in a section of a power transmission network, which section is arranged with line terminals at both ends, each terminal including impedance relays (AA, BB), including the steps of, at the occurence of a fault; measuring the apparent impedances by each relay, measuring the relaying currents, determining the type of fault, checking whether the fault involves a fault resistance or not, and, if so, solving a quadratic equation for complex numbers, resolving the quadratic equation for the real and imaginary components, obtaining two quadratic equations for a fault distance in which the coefficients are real numbers, combining the two equations and obtaining a distance to fault, or, if not so, solving a quadratic equation for real numbers, obtaining two solutions for the distance to fault d1, d2 and comparing the solutions as 0<(d1 or d2)<1 pu, where pu is the length of transmission lines between the line terminals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.