Renewable energy sources are gaining more importance in the energy scenario. The advances in the technologies associated with the increase of efficiency of solar panels, the photovoltaic (PV) solar energy has gained momentum in this new scenario. The absence of galvanic isolation in transformer less PV systems will give rise to capacitive leakage current between the photovoltaic system and the ...

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...

This paper presents a harmonics extraction algorithm using artificial intelligent method for shunt active power filter. Generally, Fourier Transform is used to analyze a distorted wave from power line and low pass filter is used to eliminate the fundamental wave before each harmonics component is detected. This conventional approach is difficult to implement due to the complicated process. In o...

The term ‘power quality’ [1-2] refers to the purity of the voltage and current wave-form, and a power quality disturbance is a deviation from the pure sinusoidal form. Harmonics superimposed on the fundamental are one cause of such deviations. Power quality problems [1-2] like voltage harmonics, voltage flickers, voltage sags and voltage swells, current harmonics, current unbalance, reactive cu...