Improved active harmonic current compensation of powerelectronic load using resonant dc link inverter

Abstract

This paper proposes an active harmonic current compensator based on Resonant DC Link Inverter (RDCLI) for sine, gle-phase systems supplying non-linear loads. This compensator is connected in parallel with any non-linear load through a filter inductance. Compensation of the line harmonics is achieved by injecting harmonic currents into the supply lines such that the compensated line current is in phase with, and of the same shape as the input voltage. The compensator is controlled by a zero-hysteresis bang-bang controller. A neW method for current initialiZation for RDCLI is proposed in this paper. A comparison with the hard-switched PWM inverter based compensator on the same platform is presented. The superior features of the proposed compensator over the PWM-based compensator in terms of efficiency, current regulator bandwidth, response time and spectral performance are established.