Fault Location on Power System Transmission Lines using Synchronized and Unsychronized Data

Abstract

Electricity supply is the brain of the civilized society, from food factories, car manufacturers, retail houses, education centers, to the corporate and entertainment industries. The reliability of a network depends on its ability and speed to sense and clear occurring faults to prevent damage to electrical equipment. This work is about the estimation of fault location on transmission power lines for timeous fault clearing and power system reconnection. Fault location has been studied over many years, resulting in numerous fault location schemes. In recent years, Phasor Measurement Units (PMUs) which provide GPS timestamped synchronized data, are used in numerous power system applications. In this study, the performance of three fault location methods using synchronized data obtained from PMUs and unsynchronized data were investigated. These are the travelling wave, negative sequence voltage and the impedance-based methods. The results have shown that fault location methods can be improved by synchronizing the data used in the fault location algorithms. For the travelling wave method, the tested cases had accuracies of less than 50% when data was not synchronized, and accuracy levels of at least 70% were achieved with data synchronization. The negative sequence voltage method improved from accuracy levels of just under 50% with unsynchronized data for tested cases to about 93% accuracy when data was synchronized. The impedance-based method showed the highest levels of accuracy for both unsynchronized and synchronized data at least 88% and 99%, respectively. The impedance-based method outperformed the other two methods.