New accurate fault location algorithm for parallel lines

A new accurate fault location algorithm for parallel lines is presented. The algorithm utilises one-end measurements of voltages and currents. Complete phase currents from both, the faulted and the healthy lines as well as phase voltages are the inputs of the fault locator. The flow of currents through the healthy line path is utilised for deriving the algorithm. Thus, the algorithm is capable of locating faults when both parallel lines are in operation. The presented algorithm is of compact form and does not require source impedances and usage of pre-fault signals is avoided. Adverse influence of uncertainty with respect to zero sequence impedance of a line is partly limited as the voltage drop across a fault path is determined excluding zero sequence components. In order to provide high accuracy of locating faults in long parallel lines the compensation for shunt capacitances is introduced. The evaluation performed by using a large number of ATP-EMTP simulations proved effectiveness and high accuracy of the presented fault location algorithm