摘要 |
Method and device for directional detection of a fault on a power transmission line located between two stations (P, Q). In one of these stations (P) there is a travelling wave model which, by means of measured currents and voltages in the station, calculates the voltage distribution along the transmission line. The direction to a fault is determined by studying changes in calculated voltages in the two stations. If a fault (F) occurs between the stations, the voltage change in one station (Q) between voltage prior to a fault and after a fault can be estimated at ¦ DELTA Uq ¦, and the corresponding voltage change in the other station (P) can be estimated at ¦ DELTA Up ¦, whereby according to the invention the difference ¦ DELTA Uq ¦ - ¦ DELTA Up ¦>0 signifies a fault on the line side of the station (P), i.e. fault lying ahead of the measuring point. |