Installation for power transmission by means of high-voltage direct current, comprising device for detection of a permanent ground fault
US5946172A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1998 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Apr 28, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/60
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An installation for power transmission by high-voltage direct current has at least two converter stations which are interconnected by a dc line (DC), at least one station (SR1) having a line protection device (LP) adapted to detect a ground fault on the dc line and, when a ground fault is detected, to achieve a reduction of the voltage (U.sub.D) and the current (I.sub.D) of the line and thereafter to make a restart attempt. The installation has, in addition, a detection circuit (FD) for detection of a permanent low-impedance ground fault on the dc line. The detection circuit is activated after an intervention by the line protection device. During a detection interval, the detection circuit causes one of the stations (SR1) to feed a current into the line. The detection circuit senses the line voltage, compares the growth of the line voltage with the corresponding expected growth in case of a faultless line and prevents a restart of the installation if the sensed voltage growth is smaller than the expected growth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.