Hammerstein Adaptive Filter Based Control Technique for Optimum Operation of a Grid Interfaced PV System

Abstract

This work presents a hammerstein adaptive filter based technique for power quality improvement of a three phase grid tied two stage solar photovoltaic system. This system provides the PV power to connected load and surplus energy to the utility. The key objective of this work, is to extract positive sequence components (PSCs) from distorted grid voltages for estimation of unit templates and proposed control extracts load current fundamental component. A feed-forward term for PV source is also introduced for enhanced dynamic response of the system. This system is examined for the conditions of unbalanced load, voltage distortions, voltage swell/sag and variable PV irradiation to prove the efficacy of the control algorithm. The system performance is acceptable and grid currents THD’s are in limits, as suggested by the IEEE-519 standard.