Fault location algorithm for multi-terminal transmission system

This chapter proposes a multi-terminal fault location algorithm for transmission lines using synchrophasors, which have a lot of applications in the modern-day power system. Due to the presence of various sources and the presence of new lines, protection challenges faced by multi-terminal transmission lines are more compared to two-terminal transmission system. However, as the modern day power system is growing rapidly, the usage of multi-terminal transmission lines is preferable owing to their advantages possessed by them compared to two-terminal transmission system. So, to protect these lines against faults, protection of lines such as fault location and identification of the faulted section is an important task in the present electricity power grid. Due to various uncertainties such as line loading and weather conditions, the line parameters may change. So, a fault location algorithm without the use of line parameters makes the algorithm more precise, reliable and accurate. In this algorithm, voltage and currents available at all the source ends are utilized to estimate the fault location. The fault location has been estimated with variations of various line lengths, fault resistances, and fault type. An optimization problem has been created further and root mean error has been introduced to find the least value among all the sections and to identify the faulted section. To reduce the % error in fault location estimation, charging current compensation is introduced. It has been observed from the results that the maximum % error in the estimation of fault location has been reduced with the charging current compensation as compared to without charging current compensation. The performance of the algorithm has also been checked for variation in synchronization errors, mutual coupling, bad data, and communication failure.