Multi-Terminal Fault Locator for Homogeneous Transmission Lines Using Extended Proportions

This paper proposes a fault location estimation algorithm for multi-terminal homogeneous transmission lines using synchronized voltage and current measurements. The algorithm can estimate the fault location using a Polynomial Equation Solution (PES) method, where the fault location is estimated with the help of sequence components of voltage and current data using extended proportions. Further, the proposed method is improved (IPES) by adopting distributed long line model equations and Taylor series to estimate the actual line parameters before estimating the modified fault location. In both the methods, fault location has been estimated without the use of line parameter data. The fault location estimation results have been provided for four terminal and five terminal networks whose mean percentage errors with IPES method are found to be 0.10% and 0.05%, which shows the preciseness of the proposed algorithm. For the considered four terminal network, analysis have been done with unsynchronized data and fault inception angle. From the analysis, it has been observed that the % error is reduced for higher synchronization errors with the inclusion of correction factors. It is also observed that the % error hasn't effected much even with higher fault inception angles.