Implementation of Adaptive Hysteresis Current Controlled Shunt Active Filter For Non-Linear Loads

Abstract: The use of nonlinear loads is increasing day by day. Application of these non-linear loads results in an increase in harmonic injection to the grid and low power factor which deteriorate the voltage quality waveforms. Active power filters (APFs) for both harmonic and reactive power compensation have found more attention in industrial applications for harmonic elimination and reactive power compensation. In this Project, an adaptive hysteresis band current controlled active power filter is implemented to eliminate harmonics at source due to three-phase rectifier. The adaptive hysteresis band current controller changes the bandwidth according to modulation frequency, supply voltage, dc capacitor voltage and slope of the reference compensator current wave thereby keeping the switching frequency constant. This controller can overcome the drawback of hysteresis current controller like switching losses, noise etc. Based on instantaneous power theory, harmonics components of load current are generated and used as reference current for APF to be compensated. The simulation of system is performed using Matlab-Simulink and Sim Power System toolbox and results are obtained

Keywords: Shunt active power filter, Harmonic Reduction, Instantaneous reactive power theory, Adaptive hysteresis current control