METHOD AND APPARATUS FOR LOCALIZING PHASE-TO-PHASE AND PHASE-TO-GROUND FAULTS IN POWER LINES

摘要

Disclosed is a method for localizing phase-to-phase and phase-to-ground faults such as short circuits in a polyphase power line. The method includes the steps of deriving three voltages u, v and w, u being proportional to the voltage of the faulty line loop, v being a reference voltage across a resistor fed by a current proportional to the faulty current, and w being a reference voltage proportional to a voltage drop in a reference length of the faulty line loop measured across a reference impedance network fed by line currents. The voltages u, y and w are integrated for a time interval chosen such that the time integral of the voltages v is null at the end of said time interval. The integrated values of the voltages u and w obtained at the end of the time interval are stored and arithmetic operations are performed on the stored values to provide information as to the location of fault. An apparatus for implementing this method is also disclosed.