This paper presents a new approach to intelligent fault diagnosis based on statistics analysis, an improved distance evaluation technique and adaptive neuro-fuzzy inference system (ANFIS). The approach consists of three stages. First, different features, including time-domain statistical characteristics, frequency-domain statistical characteristics and empirical mode decomposition (EMD) energy ...

We study automata-theoretic properties of distances and quasi-distances between words. We show that every additive distance is nite. We also show that every additive quasi-distance is regularity-preserving, that is, the neighborhood of any radius of a regular language with respect to an additive quasi-distance is regular. As an application we present a simple algorithm that constructs a metric ...

Two-dimensional, numerical models of a linear fault embedded within a linear elastic medium show the generation of off-fault tensile failure that results from inelastic slip along the fault. We explore quasistatic models with slip-weakening friction to assess the effects of spatially and temporally variable friction on the damage patterns. Tensile fractures form where tangential normal stresses...

In this paper, precise fault location in electrical traction network systems is discussed in the high-frequency domain. Based on the analysis of the equivalent impedance at the measurement terminal, the relationship between the fault distance and the frequency spectrum extreme points of the system impedance are derived. The exact fault location can be obtained from the relationship curves accor...

[1] Radiating shear and Rayleigh waves from supershear ruptures form Mach waves that transmit large-amplitude ground motion and stresses to locations far from the fault. We simulate bilateral ruptures on a finite-width vertical strike-slip fault (of width W and half-length L with L W) breaking the surface of an elastic half-space, and focus on the wavefield out to distances comparable to L. At ...

This paper deals with two new methods, based on k-NN algorithm, for fault detection and classification in distance protection. In these methods, by finding the distance between each sample and its fifth nearest neighbor in a predefault window, the fault occurrence time and the faulty phases are determined. The maximum value of the distances in case of detection and classification procedures is ...

This paper presents an improved algorithm for fault detection and classification of transmission line fault current signals using MATLAB/SIMULINK. The proposed algorithm presents a fault discrimination method based on the three-phase current and voltage waveforms measured when fault events occur in the power transmission-line network. The algorithm for fault classification employs wavelet multi...

A significant problem with current diagnostic test generation techniques is the time spent in identifying diagnostic equivalences amongst fault pairs. First, fault pair distance analysis is introduced to characterize diagnostically equivalent fault pairs. It is shown that diagnostically equivalent fault pairs are usually “close” to each other and influence the same set of primary outputs. The d...