A New Approach to Suppress DC-link Voltage Oscillations for a Grid Connected Photovoltaic System

摘要： A ?xed size perturbation in a Maximum Power Point Tracking (MPPT) algorithm yields excessive oscillations of operating point around the MPP and thus causes ?uctuations in the dc link voltage and ?ickers in the injected grid current. In this paper, we propose a new adaptive P&O MPPT by employing a Proportion-Integral (PI) controller to generate variable perturbations which eliminates the steady state error and yields faster settling time in the MPP tracking response. A comparative analysis is made using simulations in MATLAB/ Simulink ?rst then experimental studies on a prototype of grid connected PV system (GCPVS) is pursued. The obtained results are analyzed and it is found that the adaptive MPPT e?ectively reduces the dc-link voltage oscillations and injected grid current ?ickering.