Method and apparatus for measuring partial discharges in cables
US5767684A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 12, 1995 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jun 12, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/1272
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a method for detecting partial discharges occurring in a cable, wherein the cable has an earth screen with a helical structure, comprising the following steps of: arranging at least one detection coil round the cable for detecting electromagnetic pulses travelling along the cable; applying a potential difference between the core and the earth shield of the cable; and analyzing pulses generated by possible partial discharges in the at least one detection coil in order to determine the location and quality of the partial discharge having caused the pulse, wherein the detection coil is adapted to process signals with a frequency higher than 100 MHz. It has been found that with coils comprising only such a limited number of turns the signal detected by the coil is a much better representation of the form of the electromagnetic pulse travelling along the cable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.