Fuzzy Logic Controller Based THD Reduction in Non-Linear Load Using Shunt Active Filter

This paper deals with an indirect current controlled shunt active power filter (SAPF) for improving power quality by reactive power compensation and harmonic filtering. The presence of harmonics and reactive power in the power source because it will cause additional power losses and malfunctions. The proposed APF is based on a voltage source inverter (VSI). The VSI is controlled by two loops, the voltage control loop and the current control loop. The voltage control loop regulates the DC link capacitor voltage and the current control loop uses hysteresis band control to shape the source current such that it is in-phase with and of the same shape as the input voltage. The major advantage of the proposed APF is that the reference current for power quality improvement is generated from the DC link capacitor voltage. This work proposes a Fuzzy logic controller based 1-phase and 3-phase shunt active filter for THD reduction in Non-linear load. The system with control scheme is going to be analyzed in computer simulation using MATLAB/Simulink. INTRODUCTION The Harmonic distortion is one of the vital power quality problems in power systems. Theacpowersupplyfeedsdifferent-kindoflinearand non-linearloads. The non linearloads produce harmonics and reactive powerrelatedproblems.This harmonics and reactive powercause poor powerfactorand distortthe supply voltage. Thecurrentharmonicscreate a problemsinpower-systems suchasmalfunctionsinsensitiveequipment, over voltage by causesresonance and harmonic voltage drop acrossthe net-workimpedance;thatresultinpoorpower factor.