Abstract
Abstract The AC electrical distribution system works at limited values of voltage and frequency levels. The increase of using non linear loads and loads those connected by electronic keys produces non sinusoidal voltages and currents in the distribution systems. Single and three phase, controlled and uncontrolled rectifiers, are used for obtaining DC current and voltage. This affect the shape of the supply current which included many harmonics. The quality and quantity of the power obtained are affected as a result. The shape of the current wave is therefore attracted the attention of many researcher groups. The line injection by current harmonics is one of the most important and effective techniques used for such treatment. The aim of this research work is to reduce the harmonics in the input current and improving the power factor of the single phase, controlled and uncontrolled, rectifiers. This is usually carried out by employing injection method technique with reversible polarity through connecting a passive resonance circuit between the input and output of the rectifier. The passive resonance circuit creates second harmonic current which will circulate between the AC and DC sides of the rectifier and decreases the total harmonic distortion (THD). In this work, the ratio of (THD) is reduced from 50% to 10% with power factor increased nearly to unity for different values of the trigger angle (α).
