Robust control algorithm of grid interfaced solar PV system

This study presents the power quality improvement of distributed network by using robust control algorithm for a three phase grid interfaced single stage solar photovoltaic (PV) system with DSTATCOM (Distribution Static Compensator) capabilities. The functions of robust control algorithm are load balancing, reactive power compensation, power factor correction with active power generation for proposed topology. The perturb and observe algorithm is used to extract maximum power from PV array under variable insolation levels. To adapt with variation in terminal voltage at point of common contact (PCC), PV feed forward term is also added in control algorithm to make less oscillations in grid current. The advantages of control algorithm are robustness, less complex, amplitude and frequency adaptive nature. Test results demonstrate satisfactory response for steady state and dynamic conditions at load unbalancing and variations in insolation level. The distortion in grid currents and voltages are found within limits IEEE-519 standard.