A novel distance protection scheme using time-frequency analysis and pattern recognition approach

This paper presents a new approach for distance protection of transmission lines using time-frequency analysis. The proposed technique consists of preprocessing the fault current signal samples using hyperbolic S-transform to yield the change in energy and standard deviation at the appropriate window variation. From these two features, a decision of fault or no-fault on any phase or multiple phases of the transmission line can be made. The ground detection is done by a proposed indicator with a threshold value. The fault distance from the relaying point can be accurately estimated using cubic polynomial interpolation technique, Feed forward Neural Network and Adaptive Network Fuzzy Inference System (ANFIS). (C) 2006 Elsevier Ltd. All rights reserved.