Techno-economic Analysis of Non-linear DG Penetration in Radial Distribution Systems

Abstract

Increasing penetration of Distributed Generation (DG) in recentyears has presented new challenges for planning and optimal operationof integrated distribution systems. In this scenario, harmonic distortionscaused by non-linear DG operation in the distribution networks havefurther added to the complexities of regulating such interconnectedsystems. In this article, a comprehensive analysis of unbalanced radialdistribution systems (RDS) integrated with non-linear DG has been at -tempted. The analytical assessment has been carried out by consideringvarious voltage harmonics in non-linear DG in the presence of shunt ca-pacitors in the radial distribution systems. Results are obtained for TotalHarmonic Distortion (THD) of voltage and current at various buses ofthe RDS, along with harmonic power profile. An economic assessmentof annual energy loss in the presence of non-linear DG has also been at-tempted. The proposed method is tested on two IEEE radial distributionfeeders interconnected with non-linear DG. Results show that the pres-ence of even acceptable level of voltage harmonics in non-linear DG cancause severe harmonic amplification in the entire network, consequentlyleading to increased energy losses for certain harmonic orders.