In this paper, a single-ended fault location method is presented based on a circuit breaker operation using the frequencies of traveling waves. The proposed method receives the required data from voltage traveling waves with the aid of Fast Fourier Transform (FFT) and Wavelet Transform. Then, the Artificial Neural Network (ANN) identifies fault type and determines its location. In order to eval...

Many schemes are reported for shunt fault location estimation, but fault location estimation of series or open conductor faults has not been dealt with so far. The existing numerical relays only detect the open conductor (series) fault and give the indication of the faulty phase(s), but they are unable to locate the series fault. The repair crew needs to patrol the complete line to find the loc...

in this paper a novel hybrid algorithm for harmonics estimation in power systems is proposed. the estimation of the harmonic components is a nonlinear problem due to the nonlinearity of phase of sinusoids in distorted waveforms. most researchers implemented nonlinear methods to extract the harmonic parameters. however, nonlinear methods for amplitude estimation increase time of convergence. hen...

The requirements for on-line identification of system parameters have a critical needing for engineering applications, such as fault diagnosis and process detection. The classical identification methods, such as least-square method, are calculus-based search method. These methods are suffered from many problems, such as a proper initial values of the identified parameters; the objective functio...

An Iterative Learning Observer (ILO) updated successively and iteratively by immediate past system output error and ILO input is proposed for a class of time-delay nonlinear systems for the purpose of robust fault diagnosis. The proposed observer can estimate the system state as well as disturbances and actuator faults so that ILO can still track the post-fault system. In addition, the observer...

Fault diagnosis is essential for guaranteeing safe and reliable operation of complex engineering systems. Our work focuses on diagnosis of parametric faults in the components of dynamic systems, whose temporal profile can be categorized as incipient (slow) or abrupt (fast). The diagnosis of abrupt and incipient faults using qualitative approaches is challenging, since in many situations, these ...

Electrical power distribution systems are composed of heterogeneous components, which include continuous power sources, discrete relays, passive and active loads, and fastswitching power conversion subsystems. This heterogeneity introduces significant challenges for model-based diagnosis, such as building accurate models, and generating fast and accurate diagnoses while ensuring robustness to m...

This paper considers fault estimation in nonlinear fractional order systems in observer form. For this aim, a step by step second order sliding mode observer is used. By means of a fractional inequality, the stability of the observer estimation errors is analyzed and some conditions are introduced to guarantee finite time convergence of estimation errors. Finally, in a numerical example, effect...