Grid Integration Scheme for a Three Phase Single Stage Photovoltaic system employing EKF

摘要

In this work, a nonlinear Kalman filer based synchronization strategy is proposed for a single stage three phase grid tied PV system. We employed Extended Kalman Filter (EKF) to estimate the fundamental voltage components of the voltage at Point of common coupling (PCC) and the fundamental components of the load current. A Proportional-Integral (PI) controller is designed to control the DC bus capacitor voltage. Simulation and experimental studies of the proposed EKF based control scheme show that the proposed control scheme provides maximum PV power extraction and mitigates load current harmonics while reducing the Total Harmonic Distortion (THD) of the grid current and PCC voltage to a lower value these are well within the prescribed limits of IEEE 519 standards even for distorted grid voltage condition.