Digital fault location for parallel double-circuit multi-terminaltransmission lines

摘要

Two new methods are proposed for fault point location in parallelndouble-circuit multi-terminal transmission lines by using voltages andncurrents information from CCVTs and CTs at all terminal. Thesenalgorithms take advantage of the fact that the sum of currents flowingninto a fault section equals the sum of the currents at all terminals.nAlgorithm 1 employs an impedance calculation and algorithm 2 employs thencurrent diversion ratio method. Computer simulations are carried out andnapplications of the proposed methods are discussed. Both algorithms cannbe applied to all types of fault such as phase-to-ground andnphase-to-phase faults. As one equation can be used for all types ofnfault, classification of fault types and selection of faulted phase arennot required. Phase components of the line impedance are used directly,nso compensation of unbalanced line impedance is not required