Fault Location for Multi-Terminal Tapped Lines Using Synchronized Measurements

摘要

Increased penetration of distributed energy resources and their integration to the grid has given rise to huge growth in the number of multi-terminal transmission line installments. Majority of the installations do not have any measurement instruments placed at the junction, mainly to make them cost-effective. Conventional two-terminal fault location solutions fail when applied to these systems due to current infeed at the junction and lack of measurements there. This paper proposes a novel and robust fault location solution which uses positive sequence voltage and current quantities from all three terminals for accurate localization of the fault. The solution approach is to estimate the currents flowing from all three sections into the junction as a function of unknown fault distance and line parameters. The fault location is obtained by equating the sum of the three estimated currents to zero and solving for the unknown.