A fault-model-free method based on zero-crossings for locating high-impedance faults in overhead distribution networks

High-impedance faults (HIFs) location is an increasingly relevant reliability issue in the power distribution industry. The development of practical and accurate one-terminal HIF-locating methods is vital for reducing long-duration outage restoration time and cost. However, the dependency on the estimation of both fault model parameters and fault current signal can jeopardize the accuracy and practicality of existing one-terminal HIF-locating methods. This paper proposes a one-terminal fault-model-free iterative method based on zero-crossings for locating HIFs in overhead distriFbution networks. Two insights into voltage signal relationships are provided to eliminate the need for estimating fault model parameters and the fault current signal in the HIF-locating process. The first one is based on zero-crossings of the calculated voltage drop signal for estimating two parameters of the voltage signal on the fault point. The other insight is based on the zero-crossing of the voltage signal on the fault point, in which the two parameters were previously estimated, for calculating the fault distance from the kth node. Simulation results on a modified IEEE 34-node test feeder validate the high accuracy and robustness of the proposed method, considering the effect of several factors on fault distance estimation. In addition, the method convergence performance is assessed.