An impedance relation index to predict the fault locator performance considering different load models

•We present the influence of the load modeling, applied for locating faults in power distribution systems.•A relation index (α) based on the estimated impedance is proposed to predict the accuracy of a fault locator.•Tests were performed on the IEEE 34 nodes distribution system, using four different load models, all coded with ATP Models.•The load model and magnitude uncertainties affect the relation index and consequently influence the locator performance.•High α values imply low errors in fault location.

This paper aims to discuss the influence of load modeling on power system behavior and also proposes a relation index (α) based on the estimated impedance, to predict the accuracy of a fault locator. The 24.9 kV IEEE 34 nodes power distribution system modeled using ATP and considering load models as constant impedance, constant current, constant power and hybrid, all coded using ATP Models is used for tests. As a result, an analysis of the fault location using the proposed relation index is performed. The results show that both the load model and magnitude uncertainties affect the fault location and the relation index (α), which directly influence the locator performance. Finally, as it was demonstrated, high values of α imply low errors in fault location.