Transformer inrush currents were traditionally evaluated by means of Fourier analysis. Such approach affects the design of transformer differential relays concerning their immunity to inrush currents. This paper presents a statistical tool named maximum entropy method (MEM), which seems to provide a reliable and computationally efficient tool for identification inrush currents on two different ...

Power transformer is one of the most important equipment in a power transmission and distribution system. This paper presents a technology to simulate differential relay in Matlab Simulink based environment for determining its behavior during various operating conditions. The results show that this simulation method can work properly and this will allow rapid modeling and testing of new algorit...

In this work, a new approach applied to digital differential protection relay for a large power transformer is presented. First, the Fourier sine and cosine coefficients required for fundamental, second, third and fifth harmonic extraction have been determined using rectangular transfer technique. Then, these harmonics have been used in harmonics restrain and blocking techniques applied to diff...

An electronic current transformer with a B-dot sensor is proposed in this study. The B-dot sensor can realize the current measurement of the transmission line in a non-contact way in accordance with the principle of magnetic field coupling. The multiple electrodes series-opposing structure is applied together with differential input structures and active integrating circuits, which can allow th...

This paper will propose a cascade of minimum description length criterion with entropy approach along with artificial neural network (ANN) as an optimal feature extraction and selection tool for a wavelet packet transform based transformer differential protection. The proposed protection method provides a reliable and computationally efficient tool for distinguishing between internal faults and...

The doublesex-dependent sex regulatory pathway in Drosophila controls major aspects of somatic sexual differentiation, but its expression is not required in the X/X germline. Nevertheless, mutations in doublesex and in the genes that directly regulate its expression, transformer and transformer-2, disrupt early stages of oogenic differentiation to produce gonads containing immature germ cells. ...

power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. the resonant overvoltages may destroy the insulation between turns and cause to insul...

This paper presents an algorithm based on a combination of Discrete Wavelet Transforms and neural networks for detection and classification of internal faults in a twowinding three-phase transformer. Fault conditions of the transformer are simulated using ATP/EMTP in order to obtain current signals. The training process for the neural network and fault diagnosis decision are implemented using t...

This paper proposes a new algorithm for blocking the operation of Indirect Symmetrical Phase Shift Transformer (ISPST) differential relay when subjected to different operating conditions except internal fault condition. The proposed algorithm is amalgamation of Phase angle shift (PAS) threshold and Optimal Radial Basis Function Neural Network (ORBFNN). PAS between source and load side currents ...