Application of voltage source converter for power quality improvement

Abstract

This article presents an application of a four-leg voltage source converter (VSC) in a distribution network for the mitigation of power quality problems such as burden reactive power, unbalanced load, waveform distortion, and flow of high neutral currents. Fast and accurate compensation depends upon the used control algorithm for estimation of fundamental load currents. Classical theory-based enhanced phase-locked loop (EPLL) control algorithm is applied for estimation of fundamental components of distorted load current. In this algorithm, extracted fundamental load current components are applied for extraction of reference supply currents. The VSC is controlled using a digital signal processor (DSP) for implementation of control algorithm for the compensation of reactive linear and nonlinear loads. Test results on a developed VSC-based system are presented to prove the functions for improving the power quality.