Design and Implementation of Current Harmonic Filter

This article describes a design and implementation of Current Harmonic Filter (CHF) to achieve quality of power. The CHF system encompasses the DC-AC power converter, dc-link capacitor, interface inductor and Digital Signal Processor (DSP) controller. The power converter has developed through three-phase, three-wire based two-level Voltage Source Converter (VSC) topology. The control unit is deduced using Synchronous Reference Frame (SRF) method for reference current extraction and PWM-Space Vector Modulation (SVM) technique to generate switching gate pulses to drive the VSI. The entire control algorithm is coded in assembly language and executed through TMS320F240 DSP for 10 kVAR current harmonic filter. The experimental results captured the Total Harmonic Distortion (THD) of the source current, which is less than 5% under non-linear load.