Setting-free Fault Section Identification and Fault Location Method for Three-terminal Lines

Bulk industrial loads and increased installations of renewable energy sources have led to a surge in the number of multi-terminal transmission lines. Fault location on such multi-terminal lines are dominated by impedance-based methods which uses line impedance parameters of the transmission line sections as a known input. However, line impedance parameters can vary over time due to various factors and hence the values available in the database might not be up-to-date and accurate. Errors in the line impedance parameters can introduce inaccuracies in the available fault location solutions. This paper proposes a setting-free fault section identification and fault location solution for multi-terminal lines which does not require the line impedance parameters as an input. Furthermore, it also provides estimates of the impedance parameters of the main line as well as the tapped line as an output.