Control of distributed static compensator using extendedrnstructure‐enhanced phase‐locked loop–based algorithm underrnnonideal AC mains

摘要

In this paper, a 3‐phase extended structure‐enhanced phase‐locked loop (ESEPLL)–rnbased control algorithm is proposed for a 3‐phase 4‐wire DSTATCOM (distributedrnstatic compensator) at linear and/or nonlinear consumer loads. A major feature ofrnthis control algorithm includes accurate and adaptive estimation of instantaneousrnfundamental positive sequence components of load currents at nonideal AC mains.rnIn a highly distorted and highly unbalanced grid supply voltages, conventionalrnphase‐locked loop technique fails to extract the required signals. In such situation,rnthe ESEPLL technique is used for estimating the reference supply currents. Thernproposed scheme not only enhances the performance of DSTATCOM system butrnit also provides the instantaneous compensation of harmonics currents, reactivernpower, unbalancing, and neutral currents due to load behavior. A single unit ofrnESEPLL technique is used in a 3‐phase system for desired performance with necessaryrnmathematical analysis. The control algorithm is tested on DSTATCOM usingrnDSP‐d‐SPACE1103 interface with MATLAB. The obtained test results on arndeveloped prototype show that the proposed control technique succeeds to enhancernthe power quality at point of common interface under various loading conditions inrnfull‐scale voltage at distribution level.