FUZZY BASED MAXIMUM POWER POINT TRACKING IN GRID CONNECTED PV SYSTEMS UNDER PARTIALLY SHADING CONDITIONS

To convert solar energy more viable, the efficiency of solar array systems should be maximized. An easier approach to maximizing the efficiency of solar array systems is Maximum Power Point Tracking (MPPT). MPPT is used in photovoltaic (PV) systems to maximize the output power of photovoltaic array, irrespective of the irradiation and temperature conditions. Many conventional MPPT fails to attain global maximum power point due to presence of multiple maxima points in shaded solar PV panel. This work proposes a fuzzy based controller which always attains the global maximum point in shaded panels and to develop a control techniques for three phase grid connected PV system including a method for DC link voltage control that can stabilize the voltage at the inverter input. The proposed MPPT has been implemented by combining fuzzy logic based MPPT with a scanning and storing system. The proposed MPPT is able to reach the global maximum power point (MPP) under any partial shading conditions. Moreover, the controller exhibits a fast speed of convergence, having small oscillation around the MPP during steady state.