A field-circuit method for simulation of transients in a single-phase, two-winding transformer has been given. The magnetic field excited by the winding currents has been analyzed, and integral parameters have been determined. Including the equivalent circuit parameters and the magnetic residual flux in the silicon steel core, the developed method has been implemented for the transitional state...

This article presents a novel technique to distinguish between magnetizing inrush current and internal fault current of power transformer. An algorithm has been developed around the theme of the conventional differential protection method in which parallel combination of Probabilistic Neural Network (PNN) and Power Differential Protection (PDP) methods have been used. Both PNN and PDP method ar...

Thyristor rectifiers are widely used in electric railways in order to control the speed. As a consequence of their usage in addition to substantial input lead current, an enormous amount of harmonics is injected into the grid. To avoid such harmonics as well as reactive power compensation, reactive power hybrid filters consisting of active and passive filters are utilized. Regarding different p...

The purpose of this study is to generate a highly stable DC current by using a superconducting transformer. For the first trial stage, a 100 A class superconducting transformer was designed and fabricated for operation at the temperature of liquid nitrogen. The secondary coil of the transformer was wound with a superconducting Bi-2223 tape, and the turn ratio of the primary and secondary windin...

Photovoltaic(PV) systems are expected to play an important role in future energy production. An asymmetrical interleaved high step-up converter is used to get high step up gain to step up the input energy which is obtained from PV panel without operating at an extreme duty ratio. The traditional inverter which is used to convert the converter output energy from DC to AC, contains a line frequen...

Due to serious Concerns such as air pollution, global warming, and fossil fuels shortcoming, renewable energy sources photovoltaic applications are dramatically being integrated into the power generation systems all of world. Here, a new switched-capacitor-based transformer-less grid-tied inverter has been proposed. By applying series–parallel switching technique utilized switched-capacitor mod...

A high efficiency and operating life of grid feeding solar photovoltaic (PV) inverters are demanded. Because of reduced dclink capacitor requirement, current source inverter (CSI) offers higher reliability than the voltage source based solar inverter. Nonetheless, conventional three-phase pulse width modulated (PWM) current source based solar inverter injects high earth leakage current into the...

this paper presents the application of the fuzzy-neuro method toinvestigate transformer inrush current. recently, the frequency environment ofpower systems has been made more complicated and the magnitude of the secondharmonic in inrush current has been decreased because of the improvement of caststeel. therefore, traditional approaches will likely mal-operate in the case ofmagnetizing inrush w...

High-frequency loss in transformer windings using stranded wire is analyzed. A complete loss prediction method is presented. The interstrand resistivity, which is an important parameter to determine the power loss, is measured experimentally. The analytical model is solved to get an optimal pitch, which specifies the degree of twisting that results in minimum loss. A transformer using a strande...