Double-Ended Fault-Locating Method for Parallel Lines Without Measuring Parallel Line Currents

This paper introduces a novel double-ended impedance-based fault-locating method for parallel lines, effectively addressing the challenges posed by mutual coupling. Instead of directly measuring the parallel line zero-sequence current, the proposed method estimates it using synchronized currents and voltages from the local end of the faulted line and remote zero-sequence current. The proposed approach addresses field constraints where numerical relays only have this information for fault locating. The proposed phasor-based faultlocating methodology, which uses filtered data, is applicable to various parallel line topologies and can handle any number of parallel lines. Depending on the parallel line configuration, the proposed algorithm may require zero-sequence source impedance values. In case the source impedance values known to the user are inaccurate, error mitigation techniques described in this paper can be applied. This paper demonstrates the accuracy of the proposed fault-locating method through fault simulations in various parallel line configurations modelled in electromagnetic transients program (EMTP) software.