Maximizing Power Yield from Mismatched Environment in Grid-Connected PV System by Fuzzy Logic Control

Abstract

Abstract: Solar power generation is one of the suggested methods of generating renewable energy due to its vast availability. Various concerns of the grid-connected photovoltaic (PV) system occur due to fluctuation in voltage and low efficiency. A fuzzy logic-based Buck-Boost converter (FLBBC) is proposed in this paper to produce constant voltage and increase the efficiency, when the PV arrays are exposed to different irradiance. The proposed FLBBC is operated either in buck or boost mode based on the output voltage of the PV subarray. The maximum power point (MPP) trackers are employed in each subarray. This ensures that both the subarrays are operated at their respective MPPT. A fuzzy logic controller is used for generating the necessary sinusoidal duty ratios for the switches of FLBBC. The different magnitudes of power are extracted from the two subarrays and delivered to the grid. When two different magnitudes of power are supplied to the grid it is needed to maintain the grid current sinusoidal and in phase with the grid voltage. The proposed FLBBC has been validated by comprehensive simulation in MATLAB. Furthermore, FLBBC can be employed in solar farms to maximize power yield and increase efficiency.

 Index Terms: Grid connected photovoltaic system, Fuzzy logic based Buck Boost converter, Maximum power point tracker, Different irradiance, Fuzzy logic controller.