Impedance-based fault location methods: Sensitivity analysis and performance improvement

This paper deals with analysis and improvement of two-terminal impedance based fault location methods for transmission lines. Firstly, a customised sensitivity analysis (CSA) for this class of methods is discussed, which allows a more comprehensive analysis than those so far used for evaluating the robustness to uncertainties of the input parameters (such as phasors and electrical line parameters). Second, a customised modal transformation (CMT) is derived from CSA, aiming to improve impedance-based fault location methods for performance. Such an approach uses the Park transformation along with a cost function obtained from the CSA. To assess the effectiveness of the developed approach, four two-terminal fault location methods from the literature, using both distributed parameter line model and only fault data, are considered. Evaluation tests based on Alternative Transients Program (ATP) simulations have shown that the proposed approach presents results quantitatively superior than other approaches from the literature confirming its applicability.