A Fault Distance Estimation Method Based on an Adaptive Data Window for Power Network Security

Abstract

This paper presents a rapid and accurate algorithm for fault location estimation in a power transmission line. This algorithm uses the least square error (LSE) method for fault impedance estimation. After interrupting a fault, an adaptive data window technique using LSE estimates the fault impedance. Since it changes its data length according to the convergence degree of fault impedance, it can find an optimal data window length and estimate fault impedance rapidly. To prove the performance of the algorithm, the authors have tested relaying signals obtained from EMTP simulation. Test results show that the proposed algorithm estimates fault location by calculating fault impedance within a half cycle of the fault, regardless of fault type and various fault conditions. Compared to traditional techniques, it can protect parallel transmission lines more quickly and reliably.